Pioneer Series Trust Ii NCSR Certified annual shareholder report (management investment company)

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM N-CSR

CERTIFIED SHAREHOLDER REPORT OF REGISTERED

MANAGEMENT INVESTMENT COMPANIES

Investment Company Act file number 811-21460

Pioneer Series Trust II

(Exact name of registrant as specified in charter)

60 State Street, Boston, MA 02109

(Address of principal executive offices) (ZIP code)

Christopher J. Kelley, Amundi Asset Management, Inc.,

60 State Street, Boston, MA 02109

(Name and address of agent for service)

Registrant’s telephone number, including area code: (617) 742-7825

Date of fiscal year end: December 31, 2023

Date of reporting period: January 1, 2023 through December 31, 2023

Form N-CSR is to be used by management investment companies to file reports with the Commission not later than 10 days after the transmission to stockholders of any report that is required to be transmitted to stockholders under Rule 30e-1 under the Investment Company Act of 1940 (17 CFR 270.30e-1). The Commission may use the information provided on Form N-CSR in its regulatory, disclosure review, inspection, and policymaking roles.

A registrant is required to disclose the information specified by Form N-CSR, and the Commission will make this information public. A registrant is not required to respond to the collection of information contained in Form N-CSR unless the Form displays a currently valid Office of Management and Budget (“OMB”) control number. Please direct comments concerning the accuracy of the information collection burden estimate and any suggestions for reducing the burden to Secretary, Securities and Exchange Commission, 450 Fifth Street, NW, Washington, DC 20549-0609. The OMB has reviewed this collection of information under the clearance requirements of 44 U.S.C. ss. 3507.

ITEM 1. REPORTS TO STOCKHOLDERS.

Pioneer AMT-Free Municipal Fund

Annual Report | December 31, 2023


A: PBMFX	C: MNBCX	Y: PBYMX

visit us: www.amundi.com/us

Table of Contents

Portfolio Management Discussion	2
Portfolio Summary	5
Prices and Distributions	7
Performance Update	8
Comparing Ongoing Fund Expenses	11
Schedule of Investments	13
Financial Statements	27
Notes to Financial Statements	34
Report of Independent Registered Public Accounting Firm	45
Additional Information (unaudited)	47
Approval of Renewal of Investment Management Agreement	48
Trustees, Officers and Service Providers	53

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Portfolio Management Discussion | 12/31/23

Effective February 28, 2024, the Fund's portfolio managers are John (Jake) Crosby van Roden III, Managing Director and Director of Municipals, US of Amundi US and Portfolio Manager (lead portfolio manager of the Fund since February 2024); and Prakash Vadlamani, Senior Vice President, Associate Portfolio Manager and Senior Credit Analyst at Amundi US (portfolio manager of the Fund since February 2024).

Q	How did the Fund perform during the 12-month period ended December 31, 2023?
A	Pioneer AMT-Free Municipal Fund’s Class A shares returned 8.01% at net asset value (NAV) during the 12-month period ended December 31, 2023, while the Fund’s benchmark, the Bloomberg Municipal Bond Index (the Bloomberg Index), returned 6.40%. During the same period, the average return of the 170 mutual funds in Morningstar’s Municipal National Long Funds Category was 6.97%.
Q	What factors affected the Fund’s performance relative to the benchmark Bloomberg Index during the 12-month period ended December 31, 2023?
A	The Fund’s benchmark-relative outperformance for the period was 1.61%. The Fund’s long-duration positioning versus the benchmark was a key positive contributor to relative performance in the positive market environment we experienced over the twelve-month period. (Duration is a measure of the sensitivity of the price, or the value of principal, of a fixed-income investment to a change in interest rates, expressed as a number of years.) The Fund’s holdings of zero coupon tobacco Master Settlement Agreement (MSA) bonds also aided the Fund’s benchmark-relative results for the period. We have found MSA tobacco bonds to be attractive investments, not only for their potential to enhance performance, but also for the benefits received by the settling states that have issued tobacco bonds since the establishment of the MSA between the settling states and the tobacco-related companies several years ago. Those benefits have included: substantial funding for the advancement of public health; the implementation of important tobacco-related public health measures; and funding towards establishment of a national foundation dedicated to significantly reducing the use of tobacco products among youths.

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	Another positive contributor to the Fund’s benchmark-relative performance for the twelve-month period was our preference for investing in revenue bonds over general obligation (GO) issues, as revenue bonds outperformed GO’s. (Revenue bonds are backed by specific revenue streams rather than by the general revenues of the issuer.)
	On the negative side, the Fund’s overweight of AAA rated municipal bonds and underweight to A and BBB rated municipal bonds, relative to the benchmark, was a detractor.
	With regard to individual securities, the Fund’s positions in deeply discounted zero coupon tobacco MSA bonds issued by New York and California and the Florida State Turnpike Authority revenue bonds were top positive contributors to benchmark-relative returns for the period, with the performance of the bonds aided by their longer durations. Individual holdings that detracted from the Fund’s relative returns for the period included positions in bonds issued by the City of Oroville (CA) for the Oroville hospital, which lagged due to issues experienced with regard to collecting accounts receivables. The hospital has hired a consulting team to address the issue, creating what we see as a long-term investment opportunity for the bonds. Another detractor was New Hope Cultural Education Facilities Finance Corp., Cardinal Bay, Inc., Village On The Park, an assisted living facility, which is having difficulty managing cashflows.
Q	Did the Fund’s distributions* to shareholders change during the 12-month period ended December 31, 2023?
A	The Fund’s monthly distribution rate increased slightly over the 12-month period, specifically during the second quarter, reflecting the replacement of portfolio securities that had matured or been called away with municipal bonds of similar yields.
Q	Did the Fund have any exposure to derivative securities during the 12-month period ended December 31, 2023?
A	No, the Fund had no exposure to derivatives during the period.

*	Distributions are not guaranteed.

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Please refer to the Schedule of Investments on pages 13 - 26 for a full listing of Fund securities.

All investments are subject to risk, including the possible loss of principal. In the past several years, financial markets have experienced increased volatility and heightened uncertainty. The market prices of securities may go up or down, sometimes rapidly or unpredictably, due to general market conditions, such as real or perceived adverse economic, political, or regulatory conditions, recessions, inflation, changes in interest or currency rates, lack of liquidity in the bond markets, the spread of infectious illness or other public health issues, armed conflict including Russia's military invasion of Ukraine, sanctions against Russia, other nations or individuals or companies and possible countermeasures, market disruptions caused by tariffs, trade disputes or other government actions, or adverse investor sentiment. These conditions may continue, recur, worsen or spread.

The market price of securities may fluctuate when interest rates change. When interest rates rise, the prices of fixed-income securities in the Fund will generally fall. Conversely, when interest rates fall, the prices of fixed-income securities in the Fund will generally rise.

Investments in the Fund are subject to possible loss due to the financial failure of issuers of underlying securities and their inability to meet their debt obligations.

The value of municipal securities can be adversely affected by changes in financial condition of municipal issuers, lower revenues, and regulatory and political developments.

A portion of income may be subject to local, state, federal, and/or alternative minimum tax. Capital gains, if any, are subject to a capital gains tax.

At times, the Fund's investments may represent industries or sectors that are interrelated or have common risks, making them more susceptible to any economic, political, or regulatory developments or other risks affecting those industries and sectors.

These risks may increase share price volatility.

For more information on this or any Pioneer fund, please visit amundi.com/usinvestors or call 1-800-622-9876. This material must be preceded or accompanied by the Fund's current prospectus or summary prospectus.

Any information in this shareholder report regarding market or economic trends or the factors influencing the Fund’s historical or future performance are statements of opinion as of the date of this report. Past performance is not a guarantee of future results.

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Portfolio Summary | 12/31/23

Portfolio Diversification

(As a percentage of total investments)*

State Diversification

(As a percentage of total investments)*

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Portfolio Summary | 12/31/23 (continued)

10 Largest Holdings

(As a percentage of total investments)*
1.	Massachusetts Development Finance Agency, Harvard University, Series A, 5.00%, 7/15/40	3.57%
2.	U.S. Treasury Bills, 1/9/24	2.99
3.	County of Miami-Dade Water & Sewer System Revenue, Series B, 4.00%, 10/1/49	2.02
4.	Tobacco Settlement Financing Corp., Series B-1, 5.00%, 6/1/47	1.94
5.	Hillsborough County Industrial Development Authority, Tampa General Hospital, 3.50%, 8/1/55	1.93
6.	Loudoun County Economic Development Authority, Howard Hughes Medical Institute Issue, Series A, 4.00%, 10/1/52	1.81
7.	State of Ohio, Series A, 4.00%, 1/15/50	1.77
8.	Massachusetts Health & Educational Facilities Authority, Massachusetts Institute of Technology, Series K, 5.50%, 7/1/32	1.68
9.	Montgomery County Higher Education and Health Authority, Thomas Jefferson University, Series B, 4.00%, 5/1/56	1.54
10.	Massachusetts Development Finance Agency, Broad Institute, 4.00%, 4/1/41	1.42

* Excludes short-term investments and all derivative contracts except for options purchased. The Fund is actively managed, and current holdings may be different. The holdings listed should not be considered recommendations to buy or sell any securities.

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Prices and Distributions | 12/31/23

Net Asset Value per Share

Class	12/31/23	12/31/22
A	$13.28	$12.67
C	$13.17	$12.56
Y	$13.22	$12.61

Distributions per Share: 1/1/23 - 12/31/23

Class	Net Investment Income	Short-Term Capital Gains	Long-Term Capital Gains
A	$0.3820	$—	$—
C	$0.2809	$—	$—
Y	$0.4186	$—	$—

Index Definitions

The Bloomberg Municipal Bond Index is an unmanaged, broad measure of the municipal bond market. Indices are unmanaged and their returns assume reinvestment of dividends and do not reflect any fees or expenses. It is not possible to invest directly in an index.

The index defined here pertains to the “Value of $10,000 Investment” and “Value of $5 Million Investment” charts on pages 8 - 10.

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Performance Update | 12/31/23

Class A Shares

Investment Returns

The mountain chart on the right shows the change in value of a $10,000 investment made in Class A shares of Pioneer AMT-Free Municipal Fund at public offering price during the periods shown, compared to that of the Bloomberg Municipal Bond Index.

Average Annual Total Returns (As of December 31, 2023)
Period	Net Asset Value (NAV)	Public Offering Price (POP)	Bloomberg Municipal Bond Index
10 Years	2.97%	2.50%	3.03%
5 Years	1.23	0.30	2.25
1 Year	8.01	3.13	6.40

Expense Ratio
(Per prospectus dated April 1, 2023)

Gross

0.80%

Value of $10,000 Investment

Call 1-800-225-6292 or visit www.amundi.com/us for the most recent month-end performance results. Current performance may be lower or higher than the performance data quoted.

The performance data quoted represents past performance, which is no guarantee of future results. Investment return and principal value will fluctuate, and shares, when redeemed, may be worth more or less than their original cost.

NAV results represent the percent change in net asset value per share. POP returns reflect deduction of the maximum 4.50% sales charge. NAV returns would have been lower had sales charges been reflected. All results are historical and assume the reinvestment of dividends and capital gains. Other share classes are available for which performance and expenses will differ.

Performance results reflect any applicable expense waivers in effect during the periods shown. Without such waivers Fund performance would be lower. Waivers may not be in effect for all funds. Certain fee waivers are contractual through a specified period. Otherwise, fee waivers can be rescinded at any time. See the prospectus and financial statements for more information.

The performance table and graph do not reflect the deduction of fees and taxes that a shareholder would pay on Fund distributions or the redemption of Fund shares.

Please refer to the financial highlights for a more current expense ratio.

8Pioneer AMT-Free Municipal Fund | Annual Report | 12/31/23

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Performance Update | 12/31/23

Class C Shares

Investment Returns

The mountain chart on the right shows the change in value of a $10,000 investment made in Class C shares of Pioneer AMT-Free Municipal Fund during the periods shown, compared to that of the Bloomberg Municipal Bond Index.

Average Annual Total Returns (As of December 31, 2023)
Period	If Held	If Redeemed	Bloomberg Municipal Bond Index
10 Years	2.19%	2.19%	3.03%
5 Years	0.47	0.47	2.25
1 Year	7.23	6.23	6.40

Expense Ratio
(Per prospectus dated April 1, 2023)

Gross

1.57%

Value of $10,000 Investment

Call 1-800-225-6292 or visit www.amundi.com/us for the most recent month-end performance results. Current performance may be lower or higher than the performance data quoted.

Class C shares held for less than one year are also subject to a 1% contingent deferred sales charge (CDSC). “If Held” results represent the percent change in net asset value per share. “If Redeemed” returns reflect deduction of the CDSC for the one-year period, assuming a complete redemption of shares at the last price calculated on the last business day of the period, and no CDSC for the five- and 10-year periods. All results are historical and assume the reinvestment of dividends and capital gains. Other share classes are available for which performance and expenses will differ.

The performance table and graph do not reflect the deduction of fees and taxes that a shareholder would pay on Fund distributions or the redemption of Fund shares.

Please refer to the financial highlights for a more current expense ratio.

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Performance Update | 12/31/23

Class Y Shares

Investment Returns

The mountain chart on the right shows the change in value of a $5 million investment made in Class Y shares of Pioneer AMT-Free Municipal Fund during the periods shown, compared to that of the Bloomberg Municipal Bond Index.

Average Annual Total Returns (As of December 31, 2023)
Period	Net Asset Value (NAV)	Bloomberg Municipal Bond Index
10 Years	3.22%	3.03%
5 Years	1.47	2.25
1 Year	8.36	6.40

Expense Ratio (Per prospectus dated April 1, 2023)
Gross	Net
0.65%	0.49%

Value of $5 Million Investment

Call 1-800-225-6292 or visit www.amundi.com/us for the most recent month-end performance results. Current performance may be lower or higher than the performance data quoted.

Class Y shares are not subject to sales charges and are available for limited groups of eligible investors, including institutional investors. All results are historical and assume the reinvestment of dividends and capital gains. Other share classes are available for which performance and expenses will differ.

The net expense ratio reflects the contractual expense limitation currently in effect through May 1, 2025 for Class Y shares. There can be no assurance that Amundi US will extend the expense limitations beyond such time. Please see the prospectus and financial statements for more information.

Please refer to the financial highlights for more current expense ratios.

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Comparing Ongoing Fund Expenses

As a shareholder in the Fund, you incur two types of costs:

(1)	ongoing costs, including management fees, distribution and/or service (12b-1) fees, and other Fund expenses; and
(2)	transaction costs, including sales charges (loads) on purchase payments.

This example is intended to help you understand your ongoing expenses (in dollars) of investing in the Fund and to compare these costs with the ongoing costs of investing in other mutual funds. The example is based on an investment of $1,000 at the beginning of the Fund’s latest six-month period and held throughout the six months.

Using the Tables

Actual Expenses

The first table below provides information about actual account values and actual expenses. You may use the information in this table, together with the amount you invested, to estimate the expenses that you paid over the period as follows:

(1)	Divide your account value by $1,000 Example: an $8,600 account value ÷ $1,000 = 8.6
(2)	Multiply the result in (1) above by the corresponding share class’s number in the third row under the heading entitled “Expenses Paid During Period” to estimate the expenses you paid on your account during this period.

Expenses Paid on a $1,000 Investment in Pioneer AMT-Free Municipal Fund

Based on actual returns from July 1, 2023 through December 31, 2023.

Share Class	A	C	Y
Beginning Account Value on 7/1/23	$1,000.00	$1,000.00	$1,000.00
Ending Account Value (after expenses) on 12/31/23	$1,041.50	$1,037.70	$1,043.30
Expenses Paid During Period*	$4.07	$7.96	$2.52


*	Expenses are equal to the Fund’s annualized expense ratio of 0.79%, 1.55%, and 0.49% for Class A, Class C, and Class Y shares, respectively, multiplied by the average account value over the period, multiplied by 184/365 (to reﬂect the partial year period).

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Comparing Ongoing Fund Expenses (continued)

Hypothetical Example for Comparison Purposes

The table below provides information about hypothetical account values and hypothetical expenses based on the Fund’s actual expense ratio and an assumed rate of return of 5% per year before expenses, which is not the Fund’s actual return. The hypothetical account values and expenses may not be used to estimate the actual ending account balance or expenses you paid for the period.

You may use this information to compare the ongoing costs of investing in the Fund and other funds. To do so, compare this 5% hypothetical example with the 5% hypothetical examples that appear in the shareholder reports of the other funds.

Please note that the expenses shown in the tables are meant to highlight your ongoing costs only and do not reflect any transaction costs, such as sales charges (loads) that are charged at the time of the transaction. Therefore, the table below is useful in comparing ongoing costs only and will not help you determine the relative total costs of owning different funds. In addition, if these transaction costs were included, your costs would have been higher.

Expenses Paid on a $1,000 Investment in Pioneer AMT-Free Municipal Fund

Based on a hypothetical 5% return per year before expenses, reflecting the period from July 1, 2023 through December 31, 2023.

Share Class	A	C	Y
Beginning Account Value on 7/1/23	$1,000.00	$1,000.00	$1,000.00
Ending Account Value (after expenses) on 12/31/23	$1,021.22	$1,017.39	$1,022.74
Expenses Paid During Period*	$4.02	$7.88	$2.50


*	Expenses are equal to the Fund’s annualized expense ratio of 0.79%, 1.55%, and 0.49% for Class A, Class C, and Class Y shares, respectively, multiplied by the average account value over the period, multiplied by 184/365 (to reﬂect the partial year period).

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Schedule of Investments | 12/31/23

Principal Amount USD ($)		Value
	UNAFFILIATED ISSUERS — 98.6%
	Municipal Bonds — 93.9% of Net Assets(a)
	Arizona — 0.5%
6,040,000	Arizona Industrial Development Authority, 3.00%, 2/1/45	$ 4,724,971
	Total Arizona	$ 4,724,971


	California — 3.5%
10,000,000(b)	Alameda Corridor Transportation Authority, California Revenue Capital Appreciation Senior Lien, 10/1/31 (NATL Insured)	$ 7,830,700
16,695,000(b)(c)	Anaheim Public Financing Authority, Public Improvements Project, Series C, 9/1/36 (AGM Insured)	11,139,906
36,350,000(b)	California County Tobacco Securitization Agency, Capital Appreciation, Stanislaus County, Subordinated, Series D, 6/1/55	2,683,720
2,985,000	California Educational Facilities Authority, Stanford University, Series U-7, 5.00%, 6/1/46	3,678,087
2,000,000	City of Oroville, Oroville Hospital, 5.25%, 4/1/49	1,345,560
3,000,000	Long Beach Bond Finance Authority, Series A, 5.50%, 11/15/37	3,456,330
1,905,000(d)	Pomona Unified School District, Series A, 6.55%, 8/1/29 (NATL Insured)	2,071,840
	Total California	$ 32,206,143


	Colorado — 1.5%
7,040,000	Colorado Health Facilities Authority, Advent Health Obligated Group, Series A, 3.00%, 11/15/51	$ 5,177,357
5,000,000	Dominion Water & Sanitation District, 5.875%, 12/1/52	5,042,950
5,000,000	Metro Wastewater Reclamation District, Series A, 2.50%, 4/1/45	3,687,850
	Total Colorado	$ 13,908,157


	Connecticut — 0.8%
2,000,000	Mohegan Tribal Finance Authority, 7.00%, 2/1/45 (144A)	$ 2,004,400
5,985,000(d)	State of Connecticut, Series B, 2.00%, 6/1/36	4,846,833
	Total Connecticut	$ 6,851,233

The accompanying notes are an integral part of these financial statements.

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Schedule of Investments | 12/31/23 (continued)

Principal Amount USD ($)		Value
	District of Columbia — 2.1%
9,715,000	District of Columbia Tobacco Settlement Financing Corp., Asset-Backed, 6.75%, 5/15/40	$ 10,080,090
84,000,000(b)	District of Columbia Tobacco Settlement Financing Corp., Asset-Backed, Series C, 6/15/55	9,146,760
	Total District of Columbia	$ 19,226,850


	Florida — 12.3%
2,935,000	Broward County Water & Sewer Utility Revenue, Series A, 3.00%, 10/1/41	$ 2,583,240
6,145,000	County of Hillsborough, 3.00%, 8/1/41	5,384,741
7,690,000	County of Hillsborough, 3.25%, 8/1/48	6,472,442
5,375,000	County of Hillsborough Utility Revenue, 3.00%, 8/1/36	5,358,391
4,500,000	County of Hillsborough Utility Revenue, 3.00%, 8/1/37	4,165,650
3,500,000	County of Hillsborough Utility Revenue, Series A, 2.00%, 8/1/40	2,451,995
2,360,000(d)	County of Miami-Dade, Series A, 4.00%, 7/1/38	2,467,711
10,000,000	County of Miami-Dade Water & Sewer System Revenue, Series B, 3.00%, 10/1/49	7,674,400
18,500,000	County of Miami-Dade Water & Sewer System Revenue, Series B, 4.00%, 10/1/49	18,204,555
2,500,000	County of Orange, Water Utility System Revenue, 3.00%, 10/1/32	2,495,275
4,645,000	County of Orange, Water Utility System Revenue, 3.00%, 10/1/34	4,612,903
22,255,000	Hillsborough County Industrial Development Authority, Tampa General Hospital, 3.50%, 8/1/55	17,376,259
1,000,000	Sarasota County Public Hospital District, Sarasota Memorial Hospital Project, 4.00%, 7/1/48	980,880
7,485,000	South Broward Hospital District, Series A, 2.50%, 5/1/47	4,980,519
500,000	State of Florida, Department of Transportation Turnpike System Revenue, Series B, 3.00%, 7/1/49	408,965
5,000,000	State of Florida, Department of Transportation Turnpike System Revenue, Series B, 4.00%, 7/1/47	4,936,000
4,645,000(d)	State of Florida, Department Transportation Right of Way, Series A, 3.25%, 7/1/37	4,589,585
5,000,000	State of Florida Department of Transportation Turnpike System Revenue, 4.00%, 7/1/43	5,028,550
16,000,000	State of Florida Department of Transportation Turnpike System Revenue, Series C, 3.00%, 7/1/51	12,546,880
	Total Florida	$112,718,941


	Georgia — 3.4%
4,800,000	Brookhaven Development Authority, Children's Healthcare Of Atlanta, Inc., Series A, 4.00%, 7/1/44	$ 4,819,104

The accompanying notes are an integral part of these financial statements.

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Principal Amount USD ($)		Value
	Georgia — (continued)
2,040,000(d)	County of Fulton, Library Bond, 3.25%, 7/1/37	$ 1,968,314
2,870,000(d)	County of Fulton, Library Bond, 3.50%, 7/1/39	2,800,977
10,000,000	County of Fulton Water & Sewerage Revenue, Series A, 2.25%, 1/1/42	7,438,900
4,000,000	Forsyth County Water & Sewerage Authority, 3.00%, 4/1/44	3,369,640
4,000,000	Gainesville & Hall County Hospital Authority, Series A, 4.00%, 2/15/51	3,873,600
2,000,000	Main Street Natural Gas, Inc., Series A, 4.00%, 5/15/39	1,893,200
5,000,000	Metropolitan Atlanta Rapid Transit Authority, Series C, 3.50%, 7/1/38	4,882,850
	Total Georgia	$ 31,046,585


	Illinois — 1.1%
1,000,000	Illinois Finance Authority, Art Institute Of Chicago, 4.00%, 3/1/38	$ 1,011,560
1,500,000	Illinois Finance Authority, Northwestern Memorial Healthcare, Series A, 4.00%, 7/15/36	1,538,685
2,175,000	Illinois Finance Authority, Northwestern Memorial Healthcare, Series A, 4.00%, 7/15/37	2,220,066
3,000,000	Illinois Finance Authority, Northwestern Memorial Healthcare, Series A, 4.00%, 7/15/47	2,989,080
90,000	Illinois Finance Authority, Presence Health Network, Series C, 5.00%, 2/15/33	95,180
2,010,000(c)	Metropolitan Pier & Exposition Authority, Mccormick Place Convention, 7.00%, 7/1/26	2,105,998
	Total Illinois	$ 9,960,569


	Indiana — 1.1%
7,235,000	Indiana Finance Authority, Indiana University Health Obligated Group, Series A, 4.00%, 12/1/40	$ 7,178,422
3,000,000	Indiana University, Series A, 4.00%, 6/1/42	3,017,100
	Total Indiana	$ 10,195,522


	Maine — 0.5%
1,250,000	Maine Health & Higher Educational Facilities Authority, Series C, 5.125%, 7/1/52 (AGM ST AID WITHHLDG Insured)	$ 1,324,275
1,000,000	Maine Health & Higher Educational Facilities Authority, Series C, 5.50%, 7/1/47 (AGM ST AID WITHHLDG Insured)	1,086,360
1,000,000	Maine Turnpike Authority, 3.00%, 7/1/40	872,470
1,250,000	Maine Turnpike Authority, 4.00%, 7/1/45	1,245,225
	Total Maine	$ 4,528,330

The accompanying notes are an integral part of these financial statements.

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Schedule of Investments | 12/31/23 (continued)

Principal Amount USD ($)		Value
	Maryland — 2.2%
900,000(e)	Maryland Economic Development Corp., Senior Lien-Chesapeake Bay, Series A, 5.00%, 12/1/16	$ 537,750
400,000(e)	Maryland Economic Development Corp., Senior Lien-Chesapeake Bay, Series B, 5.00%, 12/1/16	239,000
3,745,000	University System of Maryland, Series A, 4.00%, 4/1/41	3,847,912
5,180,000	Washington Suburban Sanitary Commission, Consolidated Public Improvement, 3.00%, 6/1/37 (CNTY GTD Insured)	4,888,055
6,165,000	Washington Suburban Sanitary Commission, Consolidated Public Improvement, 3.00%, 6/1/45 (CNTY GTD Insured)	5,206,836
6,000,000	Washington Suburban Sanitary Commission, Consolidated Public Improvement, 3.00%, 6/1/47 (CNTY GTD Insured)	5,043,720
	Total Maryland	$ 19,763,273


	Massachusetts — 19.2%
3,485,000(d)	Cape Cod Regional Technical High School District, School Project Loan Chapter 70 B, 4.00%, 11/15/37	$ 3,597,670
3,485,000(d)	Cape Cod Regional Technical High School District, School Project Loan Chapter 70 B, 4.00%, 11/15/38	3,583,416
1,475,000(d)	City of Attleboro, Municipal Purpose Loan, 3.125%, 2/15/35	1,475,649
1,520,000(d)	City of Attleboro, Municipal Purpose Loan, 3.25%, 2/15/36	1,521,505
1,565,000(d)	City of Attleboro, Municipal Purpose Loan, 3.25%, 2/15/37	1,557,347
1,055,000(d)	City of Beverly, 3.125%, 10/15/39	961,411
3,000,000(d)	City of Quincy, 2.00%, 6/1/46	2,091,150
1,860,000(d)	City of Revere, 2.125%, 9/1/41 (ST AID WITHHLDG Insured)	1,347,775
2,000,000(d)	City of Revere, 2.25%, 9/1/43 (ST AID WITHHLDG Insured)	1,426,660
4,875,000(d)	City of Somerville, 2.125%, 10/15/40	3,686,231
4,980,000(d)	City of Somerville, 2.125%, 10/15/41	3,685,250
3,765,000(d)	City of Somerville, 4.00%, 5/1/52	3,704,722
15,000,000(d)	Commonwealth of Massachusetts, Series C, 2.75%, 3/1/50	10,928,250
1,300,000(d)	Concord & Carlisle Regional School District, 3.00%, 3/15/31	1,300,156
1,300,000(d)	Concord & Carlisle Regional School District, 3.00%, 3/15/33	1,300,078
7,345,000(d)	Dennis-Yarmouth Regional School District, 2.375%, 10/1/51	4,664,369

The accompanying notes are an integral part of these financial statements.

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Principal Amount USD ($)		Value
	Massachusetts — (continued)
1,500,000	Massachusetts Development Finance Agency, Berklee College Music, 5.00%, 10/1/35	$ 1,579,365
4,600,000	Massachusetts Development Finance Agency, Boston University, Series FF, 4.00%, 10/1/46	4,722,360
1,000,000	Massachusetts Development Finance Agency, Boston University, Series FF, 5.00%, 10/1/48	1,114,260
12,690,000	Massachusetts Development Finance Agency, Broad Institute, 4.00%, 4/1/41	12,830,859
2,000,000	Massachusetts Development Finance Agency, Broad Institute, 5.00%, 4/1/37	2,144,240
25,865,000	Massachusetts Development Finance Agency, Harvard University, Series A, 5.00%, 7/15/40	32,219,255
2,500,000	Massachusetts Development Finance Agency, Lawrence General Hospital, Series A, 5.50%, 7/1/44	2,307,575
4,000,000	Massachusetts Development Finance Agency, Lowell General Hospital, Series G, 5.00%, 7/1/44	3,998,360
400,000	Massachusetts Development Finance Agency, Milford Regional Medical Center, Series F, 5.625%, 7/15/36	396,660
500,000	Massachusetts Development Finance Agency, Milford Regional Medical Center, Series F, 5.75%, 7/15/43	469,820
450,000	Massachusetts Development Finance Agency, Northeastern University, Series A, 5.00%, 3/1/39	450,504
5,000,000	Massachusetts Development Finance Agency, Partner’s Healthcare System, 4.00%, 7/1/41	5,050,750
875,000(f)	Massachusetts Development Finance Agency, Tufts University, Series Q, 4.00%, 8/15/38	881,842
1,000,000	Massachusetts Development Finance Agency, Wellforce, Series C, 3.00%, 10/1/45 (AGM Insured)	791,160
6,600,000	Massachusetts Development Finance Agency, WGBH Educational Foundation, Series A, 5.75%, 1/1/42 (AMBAC Insured)	8,611,680
4,080,000(b)	Massachusetts Development Finance Agency, WGBH Educational Foundation, Series B, 1/1/38 (AGC Insured)	2,364,850
835,000	Massachusetts Development Finance Agency, Woods Hole Oceanographic Institution, 5.00%, 6/1/38	899,729
500,000	Massachusetts Development Finance Agency, Woods Hole Oceanographic Institution, 5.00%, 6/1/48	523,995
11,950,000	Massachusetts Health & Educational Facilities Authority, Massachusetts Institute of Technology, Series K, 5.50%, 7/1/32	15,144,952
10,000,000(d)	Town of Brookline, 3.00%, 3/15/45	8,426,600
4,000,000(d)	Town of Hingham, 2.00%, 2/15/40	2,962,240
3,000,000(d)	Town of Milford, 2.00%, 12/1/40	2,199,000
2,200,000(d)	Town of Milford, 2.125%, 12/1/48	1,443,354

The accompanying notes are an integral part of these financial statements.

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Schedule of Investments | 12/31/23 (continued)

Principal Amount USD ($)		Value
	Massachusetts — (continued)
2,000,000(d)	Town of Plymouth, Municipal Purpose Loan, 3.00%, 5/1/31	$ 1,988,700
1,535,000(d)	Town of Plymouth, Municipal Purpose Loan, 3.375%, 5/1/32	1,540,664
1,265,000(d)	Town of Plymouth, Municipal Purpose Loan, 3.50%, 5/1/35	1,269,352
3,500,000(d)	Town of Plymouth, Municipal Purpose Loan, 3.50%, 5/1/44	3,264,730
4,160,000(d)	Town of Stoughton, Municipal Purpose Loan, 3.00%, 10/15/37	3,905,574
3,000,000(d)	Town of Swampscott, 3.00%, 3/1/52	2,402,130
1,000,000(d)	Town of Wellesley, Municipal Purpose Loan, 4.00%, 6/1/41	1,004,380
2,370,000(d)	Town of Weymouth, 2.00%, 8/15/41	1,716,330
	Total Massachusetts	$175,456,909


	Michigan — 0.9%
10,000,000	Michigan State Building Authority, Series I, 3.00%, 10/15/45	$ 8,391,100
	Total Michigan	$ 8,391,100


	Minnesota — 0.5%
5,000,000	City of Rochester, Health Care Facilities, Mayo Clinic, 4.00%, 11/15/48	$ 5,012,650
	Total Minnesota	$ 5,012,650


	Missouri — 0.4%
4,000,000	Health & Educational Facilities Authority of the State of Missouri, Mercy Health, Series F, 4.00%, 11/15/45	$ 3,946,200
	Total Missouri	$ 3,946,200


	Nebraska — 1.5%
3,870,000(d)	Lancaster County School District 001, Lincoln Public Schools, 2.00%, 1/15/43	$ 2,680,285
14,750,000	University of Nebraska Facilities Corp., Green Bond, Series B, 3.00%, 7/15/54	11,344,077
	Total Nebraska	$ 14,024,362


	Nevada — 0.8%
3,500,000(d)	Las Vegas Valley Water District, Series A, 4.00%, 6/1/43	$ 3,569,685
5,000,000(d)	State of Nevada, Series A, 2.00%, 5/1/41	3,544,450
	Total Nevada	$ 7,114,135


	New Hampshire — 1.3%
5,000,000	New Hampshire Health and Education Facilities Authority Act, Series A, 5.00%, 8/1/59	$ 5,469,050

The accompanying notes are an integral part of these financial statements.

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Principal Amount USD ($)		Value
	New Hampshire — (continued)
4,000,000	New Hampshire Health and Education Facilities Authority Act, Catholic Medical Centre, 3.75%, 7/1/40	$ 3,152,440
1,185,000	New Hampshire Municipal Bond Bank, Series A, 2.50%, 2/15/47 (ST INTERCEPT Insured)	832,676
3,815,000	New Hampshire Municipal Bond Bank, Series A, 2.50%, 2/15/51 (ST INTERCEPT Insured)	2,530,604
	Total New Hampshire	$ 11,984,770


	New Jersey — 0.6%
4,000,000	New Jersey Educational Facilities Authority, Series C, 2.00%, 3/1/38	$ 3,082,800
2,100,000	New Jersey Turnpike Authority, Series B, 4.50%, 1/1/48	2,233,854
	Total New Jersey	$ 5,316,654


	New York — 5.9%
5,000,000	New York City Housing Development Corp., 3.05%, 5/1/50	$ 3,776,800
500,000	New York City Housing Development Corp., 4.80%, 2/1/53	515,475
5,000,000	New York City Housing Development Corp., Sustainability Bond, Series C, 2.75%, 2/1/51 (HUD SECT 8 FANNIE MAE Insured)	3,535,550
3,000,000	New York City Housing Development Corp., Sustainability Development Bond, Series F-1, 4.90%, 11/1/57 (REMIC FHA INS 542 (c) Insured)	3,082,110
40,000,000(b)	New York Counties Tobacco Trust, Series F, 6/1/60	2,545,600
10,000,000	New York State Dormitory Authority, Series A, 3.00%, 3/15/42	8,774,400
11,400,000	New York State Dormitory Authority, Series A, 3.00%, 7/1/48	9,113,958
1,000,000	New York State Dormitory Authority, Series A, 4.00%, 7/1/35	1,034,240
10,000,000	New York State Dormitory Authority, Columbia University, Series A-2, 5.00%, 10/1/46	12,250,200
5,515,000	New York State Dormitory Authority, Insured-FIT Student Housing Corp., 5.25%, 7/1/24 (NATL Insured)	5,531,380
1,719,516	New York State Housing Finance Agency, Series A, 1.65%, 5/15/39 (FNMA Insured)	1,301,725
1,000,000	New York State Housing Finance Agency, Series A-1, 3.95%, 11/1/60 (SONYMA Insured)	915,600
1,500,000	Port Authority of New York & New Jersey, Consolidated Ninety-Third Series, 6.125%, 6/1/94	1,514,580
	Total New York	$ 53,891,618

The accompanying notes are an integral part of these financial statements.

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Schedule of Investments | 12/31/23 (continued)

Principal Amount USD ($)		Value
	North Carolina — 1.2%
1,000,000	City of Charlotte Airport Revenue, Charlotte Douglas International Airport Revenue, Series A, 4.00%, 7/1/52	$ 1,002,820
3,000,000	City of Charlotte Storm Water Revenue, 4.00%, 12/1/43	3,025,440
3,250,000	City of Charlotte Water & Sewer System Revenue, 2.25%, 7/1/50	2,060,792
5,920,000	County of Union, Enterprise System Revenue, 3.00%, 6/1/51	4,712,557
	Total North Carolina	$ 10,801,609


	Ohio — 2.9%
8,800,000	Buckeye Tobacco Settlement Financing Authority, Senior Class 2, Series B-2, 5.00%, 6/1/55	$ 8,257,304
2,500,000	Ohio State University, Series A, 4.00%, 12/1/48	2,524,850
16,780,000	State of Ohio, Series A, 4.00%, 1/15/50	15,993,354
	Total Ohio	$ 26,775,508


	Oregon — 3.2%
5,000,000(d)	Clackamas County School District No 7J Lake Oswego, 4.00%, 6/1/43 (SCH BD GTY Insured)	$ 5,045,000
15,000,000	Medford Hospital Facilities Authority, Series A, 3.00%, 8/15/50 (AGM Insured)	11,427,000
2,000,000(b)(d)	Multnomah County School District No. 40, Deferred Interest, Series B, 6/15/30 (SCH BD GTY Insured)	1,659,160
2,000,000(b)(d)	Multnomah County School District No. 40, Deferred Interest, Series B, 6/15/31 (SCH BD GTY Insured)	1,606,340
1,715,000(b)(d)	Multnomah County School District No. 40, Deferred Interest, Series B, 6/15/32 (SCH BD GTY Insured)	1,332,624
5,000,000	Oregon Health & Science University, Green Bond, Series A, 3.00%, 7/1/51	3,932,650
5,000,000	University of Oregon, Series A, 3.50%, 4/1/52 (BAM-TCRS Insured)	4,519,900
	Total Oregon	$ 29,522,674


	Pennsylvania — 6.2%
825,000	Chester County Industrial Development Authority, Collegium Charter School, Series A, 5.125%, 10/15/37	$ 803,162
175,000	Chester County Industrial Development Authority, Collegium Charter School, Series A, 5.25%, 10/15/47	163,410
3,725,000	Delaware County Industrial Development Authority, Chester Charter School Arts Project, Series A, 5.125%, 6/1/46 (144A)	3,487,196
15,000,000	Montgomery County Higher Education and Health Authority, Thomas Jefferson University, Series B, 4.00%, 5/1/56	13,890,900

The accompanying notes are an integral part of these financial statements.

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Principal Amount USD ($)		Value
	Pennsylvania — (continued)
605,000	Pennsylvania Higher Educational Facilities Authority, Bryn Mawr College, 4.00%, 12/1/44	$ 616,477
4,750,000	Pennsylvania Higher Educational Facilities Authority, Thomas Jefferson University, Series A, 5.00%, 9/1/39	4,828,232
1,000,000	Pennsylvania Housing Finance Agency, Series 129, 3.35%, 10/1/45	846,300
2,000,000	Pennsylvania Housing Finance Agency, Series 129, 3.40%, 10/1/49	1,699,600
14,890,000	Pennsylvania Turnpike Commission, Series A, 3.00%, 12/1/51	11,356,901
10,000,000	Pennsylvania Turnpike Commission, Series A, 4.00%, 12/1/51	9,766,700
3,750,000	Philadelphia Authority for Industrial Development, Childrens Hospital Philadelphia, 4.00%, 7/1/36	3,836,175
2,500,000	Philadelphia Authority for Industrial Development, Childrens Hospital Philadelphia, 4.00%, 7/1/37	2,530,350
3,000,000	Philadelphia Authority for Industrial Development, Thomas Jefferson University, Series A, 4.00%, 9/1/42	2,959,500
	Total Pennsylvania	$ 56,784,903


	Puerto Rico — 0.2%
1,500,000	Puerto Rico Commonwealth Aqueduct & Sewer Authority, Series A, 5.00%, 7/1/47 (144A)	$ 1,443,345
	Total Puerto Rico	$ 1,443,345


	Rhode Island — 1.2%
7,050,000(g)	Tender Option Bond Trust Receipts/Certificates, RIB, Series 2019, 1.79%, 9/1/47 (144A)	$ 7,128,326
20,000,000(b)	Tobacco Settlement Financing Corp., Asset-Backed, Series B, 6/1/52	3,597,800
	Total Rhode Island	$ 10,726,126


	South Carolina — 1.0%
5,000,000(d)	County of Charleston, Series A, 2.00%, 11/1/39	$ 3,767,400
5,675,000	South Carolina Transportation Infrastructure Bank, Series A, 3.00%, 10/1/33	5,483,185
	Total South Carolina	$ 9,250,585


	Texas — 8.0%
5,000,000	Central Texas Regional Mobility Authority, Senior Lien, Series D, 3.00%, 1/1/46	$ 3,802,750
6,500,000	Central Texas Turnpike System, Series A, 3.00%, 8/15/40	5,313,230
10,000,000	City of Houston Combined Utility System Revenue, Series C, 2.50%, 11/15/40	7,967,600
10,000,000	Dallas Area Rapid Transit, Series B, 3.00%, 12/1/47	8,072,800

The accompanying notes are an integral part of these financial statements.

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Schedule of Investments | 12/31/23 (continued)

Principal Amount USD ($)		Value
	Texas — (continued)
80,000(d)	Eagle Mountain & Saginaw Independent School District, 3.00%, 8/15/29 (PSF-GTD Insured)	$ 76,956
500,000(d)	Garland Independent School District, Series A, 5.00%, 2/15/37 (PSF-GTD Insured)	592,110
400,000(d)	Garland Independent School District, Series A, 5.00%, 2/15/38 (PSF-GTD Insured)	469,496
500,000(d)	Garland Independent School District, Series A, 5.00%, 2/15/39 (PSF-GTD Insured)	582,290
1,000,000(d)	Garland Independent School District, Series A, 5.00%, 2/15/40 (PSF-GTD Insured)	1,158,620
10,000,000	Harris County Cultural Education Facilities Finance Corp., Texas Children's Hospital, 3.00%, 10/1/51	7,562,900
1,000,000	Harris County Cultural Education Facilities Finance Corp., YMCA Greater Houston Area, Series A, 5.00%, 6/1/28	993,820
500,000	Harris County Cultural Education Facilities Finance Corp., YMCA Greater Houston Area, Series A, 5.00%, 6/1/33	471,690
5,000,000(d)	Lubbock-Cooper Independent School District, 4.00%, 2/15/49 (PSF-GTD Insured)	4,991,400
2,000,000	New Hope Cultural Education Facilities Finance Corp., Cardinal Bay, Inc., Village On The Park, Series B, 4.75%, 7/1/51	720,000
5,000,000	North Texas Tollway Authority, First Tier, Series A, 3.00%, 1/1/38	4,421,550
3,500,000(d)	State of Texas, Series B, 2.125%, 8/1/38	2,716,105
10,000,000(d)	Tarrant County College District, 2.00%, 8/15/37	7,910,600
1,970,000	Texas Department of Housing & Community Affairs, Series A, 2.45%, 7/1/46 (GNMA Insured)	1,448,699
1,295,000	Texas Department of Housing & Community Affairs, Series A, 3.50%, 7/1/34 (GNMA/FNMA Insured)	1,311,136
1,625,000	Texas Department of Housing & Community Affairs, Series A, 3.80%, 7/1/39 (GNMA/FNMA Insured)	1,598,106
1,500,000	Texas Water Development Board, 4.80%, 10/15/52	1,593,795
5,000,000	Texas Water Development Board, State Revolving Fund, 3.00%, 8/1/40	4,419,400
5,000,000	Texas Water Development Board, St. Water Implementation Fund, Series A, 4.00%, 4/15/48	5,021,400
	Total Texas	$ 73,216,453


	Utah — 1.2%
13,110,000	Utah State University, Series B, 3.00%, 12/1/49	$ 10,646,893
	Total Utah	$ 10,646,893

The accompanying notes are an integral part of these financial statements.

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Principal Amount USD ($)		Value
	Virginia — 6.3%
5,340,000(d)	City of Alexandria, Series A, 3.00%, 7/15/46 (ST AID WITHHLDG Insured)	$ 4,375,810
2,425,000(d)	City of Lynchburg, 2.375%, 8/1/39	1,944,098
2,505,000(d)	City of Lynchburg, 2.375%, 8/1/40	1,969,256
2,750,000	Hampton Roads Transportation Accountability Commission, Series A, 4.00%, 7/1/57	2,689,087
5,725,000	Loudoun County Economic Development Authority, Series A, 2.125%, 12/1/39	4,303,711
15,970,000	Loudoun County Economic Development Authority, Howard Hughes Medical Institute Issue, Series A, 4.00%, 10/1/52	16,338,108
1,590,000	Loudoun County Sanitation Authority, 2.00%, 1/1/41	1,146,899
18,490,000	Tobacco Settlement Financing Corp., Series B-1, 5.00%, 6/1/47	17,535,916
8,000,000	Virginia College Building Authority, Public Higher Education Financing Program, Series C, 3.00%, 9/1/51 (ST INTERCEPT Insured)	6,354,080
650,000	Virginia Housing Development Authority, Series E, 2.10%, 7/1/35	522,971
1,000,000	Virginia Housing Development Authority, Series E, 2.30%, 7/1/40	736,950
	Total Virginia	$ 57,916,886


	Washington — 2.4%
1,025,000	Central Puget Sound Regional Transit Authority, Green Bond, Series S-1, 5.00%, 11/1/46	$ 1,216,593
10,250,000	City of Seattle Municipal Light & Power Revenue, Series A, 4.00%, 1/1/48	10,159,697
10,000,000	King County Housing Authority, Birch Creek Apartments Project, 5.50%, 5/1/38 (CNTY GTD Insured)	10,201,400
	Total Washington	$ 21,577,690


	Total Municipal Bonds (Cost $915,345,935)	$858,931,644


	U.S. Government and Agency Obligations — 4.7% of Net Assets
9,000,000(b)	U.S. Treasury Bills, 1/2/24	$ 9,000,000

The accompanying notes are an integral part of these financial statements.

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Schedule of Investments | 12/31/23 (continued)

Principal Amount USD ($)		Value
	U.S. Government and Agency Obligations — (continued)
27,000,000(b)	U.S. Treasury Bills, 1/9/24	$ 26,972,468
7,000,000(b)	U.S. Treasury Bills, 1/16/24	6,985,688
	Total U.S. Government and Agency Obligations (Cost $42,951,705)	$42,958,156


	TOTAL INVESTMENTS IN UNAFFILIATED ISSUERS — 98.6% (Cost $958,297,640)	$901,889,800
	OTHER ASSETS AND LIABILITIES — 1.4%	$ 13,213,220
	net assets — 100.0%	$ 915,103,020

AGC	Assured Guaranty Corp.
AGM	Assured Guaranty Municipal Corp.
AMBAC	Ambac Assurance Corporation.
CNTY GTD	County Guaranteed.
FNMA	Federal National Mortgage Association.
GNMA	Government National Mortgage Association.
NATL	National Public Finance Guarantee Corp.
PSF-GTD	Permanent School Fund Guaranteed.
RIB	Residual Interest Bond is purchased in a secondary market. The interest rate is subject to change periodically and inversely based upon prevailing market rates. The interest rate shown is the rate at December 31, 2023.
SCH BD GTY	School Board Guaranty.
SONYMA	State of New York Mortgage Agency.
ST AID WITHHLDG	State Aid Withholding.
ST INTERCEPT	State Aid Intercept.
(144A)	The resale of such security is exempt from registration under Rule 144A of the Securities Act of 1933. Such securities may be resold normally to qualified institutional buyers. At December 31, 2023, the value of these securities amounted to $14,063,267, or 1.5% of net assets.

(a)	Consists of Revenue Bonds unless otherwise indicated.
(b)	Security issued with a zero coupon. Income is recognized through accretion of discount.
(c)	Escrow to maturity.
(d)	Represents a General Obligation Bond.
(e)	Security is in default.

The accompanying notes are an integral part of these financial statements.

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(f)	Pre-refunded bonds have been collateralized by U.S. Treasury or U.S. Government Agency securities which are held in escrow to pay interest and principal on the tax exempt issue and to retire the bonds in full at the earliest refunding date.
(g)	The interest rate is subject to change periodically. The interest rate and/or reference index and spread shown at December 31, 2023.

The concentration of investments as a percentage of total investments by type of obligation/market sector is as follows:

Revenue Bonds:
Health Revenue	20.2%
Education Revenue	15.2
Transportation Revenue	12.1
Development Revenue	8.7
Water Revenue	5.5
Other Revenue	5.5
Tobacco Revenue	4.5
General Revenue	0.9
Power Revenue	0.6
	73.2%
General Obligation Bonds:	26.8%
	100.0%

Purchases and sales of securities (excluding short-term investments) for the year ended December 31, 2023, aggregated $148,271,096 and $464,837,775, respectively.

At December 31, 2023, the net unrealized depreciation on investments based on cost for federal tax purposes of $955,737,407 was as follows:

Aggregate gross unrealized appreciation for all investments in which there is an excess of value over tax cost	$ 26,337,841
Aggregate gross unrealized depreciation for all investments in which there is an excess of tax cost over value	(80,185,448)
Net unrealized depreciation	$(53,847,607)

The accompanying notes are an integral part of these financial statements.

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Schedule of Investments | 12/31/23 (continued)

Various inputs are used in determining the value of the Fund's investments. These inputs are summarized in the three broad levels below.

Level 1	–	unadjusted quoted prices in active markets for identical securities.
Level 2	–	other significant observable inputs (including quoted prices for similar securities, interest rates, prepayment speeds, credit risks, etc.). See Notes to Financial Statements — Note 1A.
Level 3	–	significant unobservable inputs (including the Adviser's own assumptions in determining fair value of investments). See Notes to Financial Statements — Note 1A.

The following is a summary of the inputs used as of December 31, 2023 in valuing the Fund's investments:

	Level 1	Level 2	Level 3	Total
Municipal Bonds	$—	$858,931,644	$—	$858,931,644
U.S. Government and Agency Obligations	—	42,958,156	—	42,958,156
Total Investments in Securities	$ —	$ 901,889,800	$ —	$ 901,889,800

During the year ended December 31, 2023, there were no transfers in or out of Level 3.

The accompanying notes are an integral part of these financial statements.

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Statement of Assets and Liabilities | 12/31/23

ASSETS:
Investments in unaffiliated issuers, at value (cost $958,297,640)	$ 901,889,800
Cash	3,846,174
Receivables —
Fund shares sold	2,967,446
Interest	9,718,521
Due from the Adviser	16,214
Other assets	30,555
Total assets	$ 918,468,710
LIABILITIES:
Payables —
Fund shares repurchased	$ 1,887,603
Distributions	1,083,700
Trustees' fees	1,573
Transfer agent fees	125,650
Management fees	56,774
Administrative expenses	38,997
Distribution fees	18,061
Accrued expenses	153,332
Total liabilities	$ 3,365,690
NET ASSETS:
Paid-in capital	$1,048,251,001
Distributable earnings (loss)	(133,147,981)
Net assets	$ 915,103,020
NET ASSET VALUE PER SHARE:
No par value (unlimited number of shares authorized)
Class A (based on $470,764,935/35,448,465 shares)	$ 13.28
Class C (based on $14,743,978/1,119,746 shares)	$ 13.17
Class Y (based on $429,594,107/32,498,427 shares)	$ 13.22
MAXIMUM OFFERING PRICE PER SHARE:
Class A (based on $13.28 net asset value per share/100%-4.50% maximum sales charge)	$ 13.91

The accompanying notes are an integral part of these financial statements.

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Statement of Operations FOR THE YEAR ENDED 12/31/23

INVESTMENT INCOME:
Interest from unaffiliated issuers	$ 37,295,744
Total Investment Income		$ 37,295,744
EXPENSES:
Management fees	$ 4,298,661
Administrative expenses	268,381
Transfer agent fees
Class A	216,457
Class C	7,357
Class Y	468,441
Distribution fees
Class A	1,180,560
Class C	147,228
Shareholder communications expense	108,043
Custodian fees	9,753
Registration fees	167,569
Professional fees	151,735
Printing expense	30,404
Officers' and Trustees' fees	60,588
Insurance expense	11,614
Miscellaneous	190,672
Total expenses		$ 7,317,463
Less fees waived and expenses reimbursed by the Adviser		(1,071,506)
Net expenses		$ 6,245,957
Net investment income		$ 31,049,787
REALIZED AND UNREALIZED GAIN (LOSS) ON INVESTMENTS:
Net realized gain (loss) on:
Reimbursement by the Adviser	$ 785,315
Investments in unaffiliated issuers	(53,501,463)	$(52,716,148)
Change in net unrealized appreciation (depreciation) on:
Investments in unaffiliated issuers		$ 96,259,575
Net realized and unrealized gain (loss) on investments		$ 43,543,427
Net increase in net assets resulting from operations		$ 74,593,214

The accompanying notes are an integral part of these financial statements.

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Statements of Changes in Net Assets

	Year Ended 12/31/23	Year Ended 12/31/22
FROM OPERATIONS:
Net investment income (loss)	$ 31,049,787	$ 35,015,023
Net realized gain (loss) on investments	(52,716,148)	(31,440,441)
Change in net unrealized appreciation (depreciation) on investments	96,259,575	(274,084,357)
Net increase (decrease) in net assets resulting from operations	$ 74,593,214	$ (270,509,775)
DISTRIBUTIONS TO SHAREHOLDERS:
Class A ($0.38 and $0.30 per share, respectively)	$ (14,174,645)	$ (12,418,459)
Class C ($0.28 and $0.20 per share, respectively)	(326,822)	(321,458)
Class Y ($0.42 and $0.34 per share, respectively)	(15,249,652)	(18,983,013)
Total distributions to shareholders	$ (29,751,119)	$ (31,722,930)
FROM FUND SHARE TRANSACTIONS:
Net proceeds from sales of shares	$ 382,107,020	$ 614,720,285
Reinvestment of distributions	17,575,013	16,801,547
Cost of shares repurchased	(665,098,278)	(883,618,920)
Net decrease in net assets resulting from Fund share transactions	$ (265,416,245)	$ (252,097,088)
Net decrease in net assets	$ (220,574,150)	$ (554,329,793)
NET ASSETS:
Beginning of year	$1,135,677,170	$1,690,006,963
End of year	$ 915,103,020	$1,135,677,170

The accompanying notes are an integral part of these financial statements.

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Statements of Changes in Net Assets (continued)

	Year Ended 12/31/23 Shares	Year Ended 12/31/23 Amount	Year Ended 12/31/22 Shares	Year Ended 12/31/22 Amount
Class A
Shares sold	4,489,813	$ 57,502,138	4,849,886	$ 63,996,828
Reinvestment of distributions	930,502	11,809,845	769,484	10,182,939
Less shares repurchased	(8,136,300)	(103,073,439)	(11,531,321)	(153,953,838)
Net decrease	(2,715,985)	$ (33,761,456)	(5,911,951)	$ (79,774,071)
Class C
Shares sold	212,636	$ 2,726,273	373,144	$ 4,783,991
Reinvestment of distributions	22,132	278,809	20,655	271,473
Less shares repurchased	(497,285)	(6,287,359)	(1,160,056)	(15,411,653)
Net decrease	(262,517)	$ (3,282,277)	(766,257)	$ (10,356,189)
Class Y
Shares sold	25,505,003	$ 321,878,609	41,379,537	$ 545,939,466
Reinvestment of distributions	434,257	5,486,359	475,841	6,347,135
Less shares repurchased	(43,784,143)	(555,737,480)	(53,688,995)	(714,253,429)
Net decrease	(17,844,883)	$(228,372,512)	(11,833,617)	$(161,966,828)

The accompanying notes are an integral part of these financial statements.

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Financial Highlights

	Year Ended 12/31/23	Year Ended 12/31/22	Year Ended 12/31/21	Year Ended 12/31/20	Year Ended 12/31/19
Class A
Net asset value, beginning of period	$ 12.67	$ 15.63	$ 15.70	$ 15.17	$ 14.23
Increase (decrease) from investment operations:
Net investment income (loss) (a)	$ 0.40	$ 0.34	$ 0.28	$ 0.33	$ 0.40
Net realized and unrealized gain (loss) on investments	0.59	(3.00)	(0.05)	0.68	0.95
Net increase (decrease) from investment operations	$ 0.99	$ (2.66)	$ 0.23	$ 1.01	$ 1.35
Distributions to shareholders:
Net investment income	$ (0.38)	$ (0.30)	$ (0.28)	$ (0.34)	$ (0.41)
Net realized gain	—	—	(0.02)	(0.14)	—
Total distributions	$ (0.38)	$ (0.30)	$ (0.30)	$ (0.48)	$ (0.41)
Net increase (decrease) in net asset value	$ 0.61	$ (2.96)	$ (0.07)	$ 0.53	$ 0.94
Net asset value, end of period	$ 13.28	$ 12.67	$ 15.63	$ 15.70	$ 15.17
Total return (b)	8.01%(c)	(17.05)%	1.45%	6.75%	9.57%
Ratio of net expenses to average net assets	0.79%	0.78%	0.79%	0.80%	0.81%
Ratio of net investment income (loss) to average net assets	3.14%	2.49%	1.80%	2.13%	2.70%
Portfolio turnover rate	16%	21%	3%	29%	10%
Net assets, end of period (in thousands)	$470,765	$483,373	$688,823	$740,589	$634,233
Ratios with no waiver of fees and assumption of expenses by the Adviser and no reduction for fees paid indirectly:
Total expenses to average net assets	0.85%	0.80%	0.79%	0.80%	0.81%
Net investment income (loss) to average net assets	3.08%	2.47%	1.80%	2.13%	2.70%

(a)	The per-share data presented above is based on the average shares outstanding for the period presented.
(b)	Assumes initial investment at net asset value at the beginning of each period, reinvestment of all distributions, the complete redemption of the investment at net asset value at the end of each period and no sales charges. Total return would be reduced if sales charges were taken into account.
(c)	For the year ended December 31, 2023, the Fund's total return includes a reimbursement by the Adviser (see Notes to the Financial Statements-Note 1.B). Without reimbursement, Class A's total return would have been 7.93%.

The accompanying notes are an integral part of these financial statements.

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Financial Highlights (continued)

	Year Ended 12/31/23	Year Ended 12/31/22	Year Ended 12/31/21	Year Ended 12/31/20	Year Ended 12/31/19
Class C
Net asset value, beginning of period	$ 12.56	$ 15.49	$ 15.56	$ 15.04	$ 14.11
Increase (decrease) from investment operations:
Net investment income (loss) (a)	$ 0.30	$ 0.23	$ 0.16	$ 0.21	$ 0.29
Net realized and unrealized gain (loss) on investments	0.59	(2.96)	(0.05)	0.67	0.93
Net increase (decrease) from investment operations	$ 0.89	$ (2.73)	$ 0.11	$ 0.88	$ 1.22
Distributions to shareholders:
Net investment income	$ (0.28)	$ (0.20)	$ (0.16)	$ (0.22)	$ (0.29)
Net realized gain	—	—	(0.02)	(0.14)	—
Total distributions	$ (0.28)	$ (0.20)	$ (0.18)	$ (0.36)	$ (0.29)
Net increase (decrease) in net asset value	$ 0.61	$ (2.93)	$ (0.07)	$ 0.52	$ 0.93
Net asset value, end of period	$ 13.17	$ 12.56	$ 15.49	$ 15.56	$ 15.04
Total return (b)	7.23%(c)	(17.68)%	0.70%	5.92%	8.74%
Ratio of net expenses to average net assets	1.55%	1.55%	1.53%	1.55%	1.56%
Ratio of net investment income (loss) to average net assets	2.38%	1.68%	1.06%	1.36%	1.95%
Portfolio turnover rate	16%	21%	3%	29%	10%
Net assets, end of period (in thousands)	$14,744	$17,357	$33,280	$40,763	$30,294
Ratios with no waiver of fees and assumption of expenses by the Adviser and no reduction for fees paid indirectly:
Total expenses to average net assets	1.60%	1.57%	1.53%	1.55%	1.56%
Net investment income (loss) to average net assets	2.33%	1.66%	1.06%	1.36%	1.95%

(a)	The per-share data presented above is based on the average shares outstanding for the period presented.
(b)	Assumes initial investment at net asset value at the beginning of each period, reinvestment of all distributions, the complete redemption of the investment at net asset value at the end of each period and no sales charges. Total return would be reduced if sales charges were taken into account.
(c)	For the year ended December 31, 2023, the Fund's total return includes a reimbursement by the Adviser (see Notes to the Financial Statements-Note 1.B). Without reimbursement, Class C's total return would have been 7.14%.

The accompanying notes are an integral part of these financial statements.

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	Year Ended 12/31/23	Year Ended 12/31/22	Year Ended 12/31/21	Year Ended 12/31/20	Year Ended 12/31/19
Class Y
Net asset value, beginning of period	$ 12.61	$ 15.57	$ 15.63	$ 15.13	$ 14.19
Increase (decrease) from investment operations:
Net investment income (loss) (a)	$ 0.44	$ 0.37	$ 0.32	$ 0.36	$ 0.44
Net realized and unrealized gain (loss) on investments	0.59	(2.99)	(0.04)	0.66	0.95
Net increase (decrease) from investment operations	$ 1.03	$ (2.62)	$ 0.28	$ 1.02	$ 1.39
Distributions to shareholders:
Net investment income	$ (0.42)	$ (0.34)	$ (0.32)	$ (0.38)	$ (0.45)
Net realized gain	—	—	(0.02)	(0.14)	—
Total distributions	$ (0.42)	$ (0.34)	$ (0.34)	$ (0.52)	$ (0.45)
Net increase (decrease) in net asset value	$ 0.61	$ (2.96)	$ (0.06)	$ 0.50	$ 0.94
Net asset value, end of period	$ 13.22	$ 12.61	$ 15.57	$ 15.63	$ 15.13
Total return (b)	8.36%(c)	(16.88)%	1.77%	6.82%	9.87%
Ratio of net expenses to average net assets	0.49%	0.49%	0.53%	0.55%	0.55%
Ratio of net investment income (loss) to average net assets	3.43%	2.78%	2.05%	2.36%	2.94%
Portfolio turnover rate	16%	21%	3%	29%	10%
Net assets, end of period (in thousands)	$429,594	$634,946	$967,904	$842,214	$652,890
Ratios with no waiver of fees and assumption of expenses by the Adviser and no reduction for fees paid indirectly:
Total expenses to average net assets	0.66%	0.65%	0.59%	0.62%	0.62%
Net investment income (loss) to average net assets	3.26%	2.62%	1.99%	2.29%	2.87%

(a)	The per-share data presented above is based on the average shares outstanding for the period presented.
(b)	Assumes initial investment at net asset value at the beginning of each period, reinvestment of all distributions and the complete redemption of the investment at net asset value at the end of each period.
(c)	For the year ended December 31, 2023, the Fund's total return includes a reimbursement by the Adviser (see Notes to the Financial Statements-Note 1.B). Without reimbursement, Class Y's total return would have been 8.28%.

The accompanying notes are an integral part of these financial statements.

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Notes to Financial Statements | 12/31/23

1. Organization and Signiﬁcant Accounting Policies

Pioneer AMT-Free Municipal Fund (the “Fund”) is one of two series comprising Pioneer Series Trust II (the “Trust”), a Delaware statutory trust. The Fund is registered under the Investment Company Act of 1940, as amended (the "1940 Act") as a diversified, open-end management investment company. The investment objective of the Fund is to seek a high level of current income exempt from federal income tax as is consistent with the relative stability of capital.

The Fund offers four classes of shares designated as Class A, Class C, Class K and Class Y shares. Class K shares had not commenced operations as of December 31, 2023. Each class of shares represents an interest in the same portfolio of investments of the Fund and has identical rights (based on relative net asset values) to assets and liquidation proceeds. Share classes can bear different rates of class-speciﬁc fees and expenses, such as transfer agent and distribution fees. Differences in class-speciﬁc fees and expenses will result in differences in net investment income and, therefore, the payment of different dividends from net investment income earned by each class. The Amended and Restated Declaration of Trust of the Trust gives the Board of Trustees the ﬂexibility to specify either per-share voting or dollar-weighted voting when submitting matters for shareholder approval. Under per-share voting, each share of a class of the Fund is entitled to one vote. Under dollar-weighted voting, a shareholder’s voting power is determined not by the number of shares owned, but by the dollar value of the shares on the record date. Each share class has exclusive voting rights with respect to matters affecting only that class, including with respect to the distribution plan for that class. There is no distribution plan for Class K or Class Y shares.

Amundi Asset Management US, Inc., an indirect, wholly owned subsidiary of Amundi and Amundi’s wholly owned subsidiary, Amundi USA, Inc., serves as the Fund’s investment adviser (the “Adviser”). Amundi Distributor US, Inc., an afﬁliate of the Adviser, serves as the Fund’s distributor (the “Distributor”).

The Fund is required to comply with Rule 18f-4 under the 1940 Act, which governs the use of derivatives by registered investment companies. Rule 18f-4 permits funds to enter into derivatives transactions (as defined in Rule 18f-4) and certain other transactions notwithstanding the restrictions on the issuance of “senior securities” under Section 18 of the 1940 Act. Rule 18f-4 requires a fund to establish and maintain a comprehensive derivatives risk management program, appoint a derivatives

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risk manager and comply with a relative or absolute limit on fund leverage risk calculated based on value-at-risk (“VaR”), unless the Fund uses derivatives in only a limited manner (a "limited derivatives user"). The Fund is currently a limited derivatives user for purposes of Rule 18f-4.

The Fund is an investment company and follows investment company accounting and reporting guidance under U.S. Generally Accepted Accounting Principles (“U.S. GAAP”). U.S. GAAP requires the management of the Fund to make estimates and assumptions that affect the reported amounts of assets and liabilities, the disclosure of contingent assets and liabilities at the date of the ﬁnancial statements, and the reported amounts of income, expenses and gain or loss on investments during the reporting period. Actual results could differ from those estimates.

The following is a summary of signiﬁcant accounting policies followed by the Fund in the preparation of its ﬁnancial statements:

A.	Security Valuation
	The net asset value of the Fund is computed once daily, on each day the New York Stock Exchange (“NYSE”) is open, as of the close of regular trading on the NYSE.
	Fixed-income securities are valued by using prices supplied by independent pricing services, which consider such factors as market prices, market events, quotations from one or more brokers, Treasury spreads, yields, maturities and ratings, or may use a pricing matrix or other fair value methods or techniques to provide an estimated value of the security or instrument. A pricing matrix is a means of valuing a debt security on the basis of current market prices for other debt securities, historical trading patterns in the market for fixed-income securities and/or other factors. Non-U.S. debt securities that are listed on an exchange will be valued at the bid price obtained from an independent third party pricing service. When independent third party pricing services are unable to supply prices, or when prices or market quotations are considered to be unreliable, the value of that security may be determined using quotations from one or more broker-dealers.
	Securities for which independent pricing services or broker-dealers are unable to supply prices or for which market prices and/or quotations are not readily available or are considered to be unreliable are valued by a fair valuation team comprised of certain personnel of the Adviser. The Adviser is designated as the valuation designee for the Fund pursuant to Rule 2a-5 under the 1940 Act. The Adviser’s fair valuation team is responsible for monitoring developments that may impact fair valued securities.

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	Inputs used when applying fair value methods to value a security may include credit ratings, the financial condition of the company, current market conditions and comparable securities. The Adviser may use fair value methods if it is determined that a significant event has occurred after the close of the exchange or market on which the security trades and prior to the determination of the Fund's net asset value. Examples of a significant event might include political or economic news, corporate restructurings, natural disasters, terrorist activity or trading halts. Thus, the valuation of the Fund's securities may differ significantly from exchange prices, and such differences could be material.
B.	Investment Income and Transactions
	Interest income, including interest on income-bearing cash accounts, is recorded on the accrual basis. Dividend and interest income are reported net of unrecoverable foreign taxes withheld at the applicable country rates and net of income accrued on defaulted securities.
	Interest and dividend income payable by delivery of additional shares is reclassified as PIK (payment-in-kind) income upon receipt and is included in interest and dividend income, respectively.
	Security transactions are recorded as of trade date. Gains and losses on sales of investments are calculated on the identified cost method for both financial reporting and federal income tax purposes.
	During the fiscal year ended December 31, 2023, the Fund realized a loss of $785,315 due to an operational error. The Adviser voluntarily reimbursed the Fund for this loss, which is reflected on the Statement of Operations as Reimbursement by the Adviser.
C.	Federal Income Taxes
	It is the Fund's policy to comply with the requirements of the Internal Revenue Code applicable to regulated investment companies and to distribute all of its net taxable income and net realized capital gains, if any, to its shareholders. Therefore, no provision for federal income taxes is required. As of December 31, 2023, the Fund did not accrue any interest or penalties with respect to uncertain tax positions, which, if applicable, would be recorded as an income tax expense on the Statement of Operations. Tax returns filed within the prior three years remain subject to examination by federal and state tax authorities.
	The amount and character of income and capital gain distributions to shareholders are determined in accordance with federal income tax rules, which may differ from U.S. GAAP. Distributions in excess of net

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	investment income or net realized gains are temporary over distributions for financial statement purposes resulting from differences in the recognition or classification of income or distributions for financial statement and tax purposes. Capital accounts within the financial statements are adjusted for permanent book/tax differences to reflect tax character, but are not adjusted for temporary differences.
	At December 31, 2023, the Fund was permitted to carry forward indefinitely $3,596,446 of short-term losses and $79,568,231 of long-term losses.
	The tax character of distributions paid during the years ended December 31, 2023 and December 31, 2022, was as follows:

	2023	2022
Distributions paid from:
Tax-exempt income	$29,163,529	$31,249,062
Ordinary income	587,590	473,868
Total	$29,751,119	$31,722,930

The following shows the components of distributable earnings (losses) on a federal income tax basis at December 31, 2023:

	2023
Distributable earnings/(losses):
Undistributed tax-exempt income	$ 3,864,303
Capital loss carryforward	(83,164,677)
Net unrealized depreciation	(53,847,607)
Total	$(133,147,981)

The difference between book-basis and tax-basis unrealized depreciation is attributable to the tax treatment of premium and amortization, wash sales and tax adjustments on defaulted bonds.

D.	Fund Shares
	The Fund records sales and repurchases of its shares as of trade date. The Distributor earned $6,290 in underwriting commissions on the sale of Class A shares during the year ended December 31, 2023.
E.	Class Allocations
	Income, common expenses and realized and unrealized gains and losses are calculated at the Fund level and allocated daily to each class of shares based on its respective percentage of adjusted net assets at the beginning of the day.

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	Distribution fees are calculated based on the average daily net asset value attributable to Class A and Class C shares of the Fund, respectively (see Note 5). Class Y shares do not pay distribution fees. All expenses and fees paid to the Fund's transfer agent for its services are allocated among the classes of shares based on the number of accounts in each class and the ratable allocation of related out-of-pocket expenses (see Note 4).
	The Fund declares as daily dividends substantially all of its net investment income. All dividends are paid on a monthly basis. Short-term capital gain distributions, if any, may be declared with the daily dividends. Distributions to shareholders are recorded as of the ex-dividend date. Distributions paid by the Fund with respect to each class of shares are calculated in the same manner and at the same time, except that net investment income dividends to Class A, Class C and Class Y shares can reflect different transfer agent and distribution expense rates.
F.	Risks
	The value of securities held by the Fund may go up or down, sometimes rapidly or unpredictably, due to general market conditions, such as real or perceived adverse economic, political or regulatory conditions, recessions, the spread of infectious illness or other public health issues, inflation, changes in interest rates, armed conflict such as between Russia and Ukraine or in the Middle East, sanctions against Russia, other nations or individuals or companies and possible countermeasures, lack of liquidity in the bond markets or adverse investor sentiment. In the past several years, financial markets have experienced increased volatility, depressed valuations, decreased liquidity and heightened uncertainty. These conditions may continue, recur, worsen or spread. Inflation and interest rates have increased and may rise further. These circumstances could adversely affect the value and liquidity of the Fund's investments and negatively impact the Fund's performance.
	The long-term impact of the COVID-19 pandemic and its subsequent variants on economies, markets, industries and individual issuers, are not known. Some sectors of the economy and individual issuers have experienced or may experience particularly large losses. Periods of extreme volatility in the financial markets, reduced liquidity of many instruments, increased government debt, inflation, and disruptions to supply chains, consumer demand and employee availability, may continue for some time. Following Russia's invasion of Ukraine, Russian securities lost all, or nearly all, their market value. Other securities or

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	markets could be similarly affected by past or future political, geopolitical or other events or conditions.
	Governments and central banks, including the U.S. Federal Reserve, have taken extraordinary and unprecedented actions to support local and global economies and the financial markets. These actions have resulted in significant expansion of public debt, including in the U.S. The consequences of high public debt, including its future impact on the economy and securities markets, may not be known for some time.
	The U.S. and other countries are periodically involved in disputes over trade and other matters, which may result in tariffs, investment restrictions and adverse impacts on affected companies and securities. For example, the U.S. has imposed tariffs and other trade barriers on Chinese exports, has restricted sales of certain categories of goods to China, and has established barriers to investments in China. Trade disputes may adversely affect the economies of the U.S. and its trading partners, as well as companies directly or indirectly affected and financial markets generally. If the political climate between the U.S. and China does not improve or continues to deteriorate, if China were to attempt unification of Taiwan by force, or if other geopolitical conflicts develop or get worse, economies, markets and individual securities may be severely affected both regionally and globally, and the value of the Fund's assets may go down.
	At times, the Fund’s investments may represent industries or industry sectors that are interrelated or have common risks, making the Fund more susceptible to any economic, political, or regulatory developments or other risks affecting those industries and sectors.
	The market prices of the Fund's fixed income securities may fluctuate significantly when interest rates change. The value of your investment will generally go down when interest rates rise. A rise in rates tends to have a greater impact on the prices of longer term or duration securities. For example, if interest rates increase by 1%, the value of a Fund's portfolio with a portfolio duration of ten years would be expected to decrease by 10%, all other things being equal. In recent years interest rates and credit spreads in the U.S. have been at historic lows. The U.S. Federal Reserve has raised certain interest rates, and interest rates may continue to go up. A general rise in interest rates could adversely affect the price and liquidity of fixed income securities. The maturity of a security may be significantly longer than its effective duration. A security's maturity and other features may be more relevant than its effective duration in determining the security's sensitivity to other factors affecting the issuer or markets generally, such as changes in

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	credit quality or in the yield premium that the market may establish for certain types of securities (sometimes called "credit spread"). In general, the longer its maturity the more a security may be susceptible to these factors. When the credit spread for a fixed income security goes up, or "widens," the value of the security will generally go down.
	If an issuer or guarantor of a security held by the Fund or a counterparty to a financial contract with the Fund defaults on its obligation to pay principal and/or interest, has its credit rating downgraded or is perceived to be less creditworthy, or the credit quality or value of any underlying assets declines, the value of your investment will typically decline. Changes in actual or perceived creditworthiness may occur quickly. The Fund could be delayed or hindered in its enforcement of rights against an issuer, guarantor or counterparty.
	The municipal bond market can be susceptible to unusual volatility, particularly for lower-rated and unrated securities. Liquidity can be reduced unpredictably in response to overall economic conditions or credit tightening. Municipal issuers may be adversely affected by rising health care costs, increasing unfunded pension liabilities, and by the phasing out of federal programs providing financial support. Unfavorable conditions and developments relating to projects financed with municipal securities can result in lower revenues to issuers of municipal securities, potentially resulting in defaults. Issuers often depend on revenues from these projects to make principal and interest payments. The value of municipal securities can also be adversely affected by changes in the financial condition of one or more individual municipal issuers or insurers of municipal issuers, regulatory and political developments, tax law changes or other legislative actions, and by uncertainties and public perceptions concerning these and other factors. Municipal securities may be more susceptible to down-grades or defaults during recessions or similar periods of economic stress. Financial difficulties of municipal issuers may continue or get worse, particularly in the event of economic or market turmoil or a recession. To the extent the Fund invests significantly in a single state (including California and Massachusetts), city, territory (including Puerto Rico), or region, or in securities the payments on which are dependent upon a single project or source of revenues, or that relate to a sector or industry, including health care facilities, education, transportation, special revenues and pollution control, the Fund will be more susceptible to associated risks and developments.
	The Fund may invest up to 10% of its net assets in below-investment-grade (high-yield) debt securities. Some of these high-yield securities may be convertible into equity securities of the issuer. Debt securities

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	rated below-investment-grade are commonly referred to as “junk bonds” and are considered speculative with respect to the issuer’s capacity to pay interest and repay principal. These securities involve greater risk of loss, are subject to greater price volatility, and may be less liquid and more difficult to value, especially during periods of economic uncertainty or change, than higher rated debt securities.
	With the increased use of technologies such as the Internet to conduct business, the Fund is susceptible to operational, information security and related risks. While the Fund’s Adviser has established business continuity plans in the event of, and risk management systems to prevent, limit or mitigate, such cyber-attacks, there are inherent limitations in such plans and systems, including the possibility that certain risks have not been identified. Furthermore, the Fund cannot control the cybersecurity plans and systems put in place by service providers to the Fund such as the Fund's custodian and accounting agent, and the Fund’s transfer agent. In addition, many beneficial owners of Fund shares hold them through accounts at broker-dealers, retirement platforms and other financial market participants over which neither the Fund nor the Adviser exercises control. Each of these may in turn rely on service providers to them, which are also subject to the risk of cyber-attacks. Cybersecurity failures or breaches at the Adviser or the Fund’s service providers or intermediaries have the ability to cause disruptions and impact business operations, potentially resulting in financial losses, interference with the Fund’s ability to calculate its net asset value, impediments to trading, the inability of Fund shareholders to effect share purchases, redemptions or exchanges or receive distributions, loss of or unauthorized access to private shareholder information and violations of applicable privacy and other laws, regulatory fines, penalties, reputational damage, or additional compliance costs. Such costs and losses may not be covered under any insurance. In addition, maintaining vigilance against cyber-attacks may involve substantial costs over time, and system enhancements may themselves be subject to cyber-attacks.
	The Fund’s prospectus contains unaudited information regarding the Fund’s principal risks. Please refer to that document when considering the Fund’s principal risks.

2. Management Agreement

The Adviser manages the Fund’s portfolio. Management fees payable under the Fund’s Investment Management Agreement with the Adviser are calculated daily and paid monthly at the annual rate of 0.50% of the Fund’s average daily net assets up to $250 million, 0.45% of the next

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$500 million of the Fund’s average daily net assets, 0.40% of the next $1.25 billion of the Fund’s average daily net assets, and 0.35% of the Fund’s average daily net assets over $2 billion. For the year ended December 31, 2023, the effective management fee (excluding waivers and/or assumption of expenses) was equivalent to 0.45% of the Fund’s average daily net assets.

The Adviser has contractually agreed to limit ordinary operating expenses (ordinary operating expenses means all fund expenses other than taxes, brokerage commissions, acquired fund fees and expenses and extraordinary expenses, such as litigation) to the extent required to reduce Fund expenses to 0.49% of the average daily net assets attributable to Class Y shares. This expense limitation is in effect through May 1, 2025. There can be no assurance that the Adviser will extend the expense limitation agreement for a class of shares beyond the date referred to above. Fees waived and expenses reimbursed during the year ended December 31, 2023 are reflected on the Statement of Operations.

In addition, under the management and administration agreements, certain other services and costs, including accounting, regulatory reporting and insurance premiums, are paid by the Fund as administrative reimbursements. Reflected on the Statement of Assets and Liabilities is $56,774 in management fees payable to the Adviser at December 31, 2023.

3. Compensation of Officers and Trustees

The Fund pays an annual fee to its Trustees. The Adviser reimburses the Fund for fees paid to the Interested Trustees. Except for the chief compliance officer, the Fund does not pay any salary or other compensation to its officers. The Fund pays a portion of the chief compliance officer's compensation for his services as the Fund's chief compliance officer. Amundi US pays the remaining portion of the chief compliance officer's compensation. For the year ended December 31, 2023, the Fund paid $60,588 in Officers' and Trustees' compensation, which is reflected on the Statement of Operations as Officers' and Trustees' fees. At December 31, 2023, on its Statement of Assets and Liabilities, the Fund had a payable for Trustees' fees of $1,573 and a payable for administrative expenses of $38,997, which includes the payable for Officers' compensation.

4. Transfer Agent

BNY Mellon Investment Servicing (US) Inc. serves as the transfer agent to the Fund at negotiated rates. Transfer agent fees and payables shown on the Statement of Operations and the Statement of Assets and Liabilities, respectively, include sub-transfer agent expenses incurred through the Fund’s omnibus relationship contracts.

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In addition, the Fund reimbursed the transfer agent for out-of-pocket expenses incurred by the transfer agent related to shareholder communications activities such as proxy and statement mailings, and outgoing phone calls. For the year ended December 31, 2023, such out-of-pocket expenses by class of shares were as follows:

Shareholder Communications:
Class A	$ 33,395
Class C	936
Class Y	73,712
Total	$108,043

5. Distribution Plan

The Fund has adopted a distribution plan (the “Plan”) pursuant to Rule 12b-1 under the 1940 Act with respect to its Class A and Class C shares. Pursuant to the Plan, the Fund pays the Distributor 0.25% of the Fund's average daily net assets attributable to Class A shares as compensation for personal services and/or account maintenance services or distribution services with regard to Class A shares. Pursuant to the Plan, the Fund also pays the Distributor 1.00% of the average daily net assets attributable to Class C shares. The fee for Class C shares consists of a 0.25% service fee and a 0.75% distribution fee paid as compensation for personal services and/or account maintenance services or distribution services with regard to Class C shares. Reflected on the Statement of Assets and Liabilities is $18,061 in distribution fees payable to the Distributor at December 31, 2023.

In addition, redemptions of Class A and Class C shares may be subject to a contingent deferred sales charge (“CDSC”). A CDSC of 1.00% may be imposed on redemptions of certain net asset value purchases of Class A shares within 12 months of purchase. Redemptions of Class C shares within 12 months of purchase are subject to a CDSC of 1.00% based on the lower of cost or market value of shares being redeemed. Shares purchased as part of an exchange remain subject to any CDSC that applied to the original purchase of those shares. There is no CDSC for Class Y shares. Proceeds from the CDSCs are paid to the Distributor. For the year ended December 31, 2023, CDSCs in the amount of $17,147 were paid to the Distributor.

6. Line of Credit Facility

The Fund, along with certain other funds in the Pioneer Family of Funds, participates in a committed, unsecured revolving line of credit (“credit facility”). Borrowings are used solely for temporary or emergency purposes. The Fund may borrow up to the lesser of the amount available under the

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credit facility or the limits set for borrowing by the Fund’s prospectus and the 1940 Act. During the fiscal year ended December 31, 2023, the Fund participated in a credit facility in the amount of $380 million. Under such credit facility, depending on the type of loan, interest on borrowings was payable at the Secured Overnight Financing Rate ("SOFR") plus a credit spread. The Fund also paid both an upfront fee and an annual commitment fee to participate in the credit facility. The upfront fee in the amount of 0.15% of the total credit facility and the commitment fee in the amount of 0.30% of the daily unused portion of each lender's commitment were allocated among participating funds based on an allocation schedule set forth in the credit facility. For the year ended December 31, 2023, the Fund had no borrowings under the credit facility.

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Report of Independent Registered Public Accounting Firm

To the Board of Trustees of Pioneer Series Trust II and the Shareholders of Pioneer AMT-Free Municipal Fund:

Opinion on the Financial Statements

We have audited the accompanying statement of assets and liabilities of Pioneer AMT-Free Municipal Fund (the “Fund”) (one of the funds constituting Pioneer Series Trust II (the “Trust”)), including the schedule of investments, as of December 31, 2023, and the related statement of operations for the year then ended, the statements of changes in net assets for each of the two years in the period then ended, the financial highlights for each of the five years in the period then ended and the related notes (collectively referred to as the “financial statements”). In our opinion, the financial statements present fairly, in all material respects, the financial position of the Fund (one of the funds constituting Pioneer Series Trust II) at December 31, 2023, the results of its operations for the year then ended, the changes in its net assets for each of the two years in the period then ended, and its financial highlights for each of the five years in the period then ended in conformity with U.S. generally accepted accounting principles.

Basis for Opinion

These financial statements are the responsibility of the Trust’s management. Our responsibility is to express an opinion on the Fund’s financial statements based on our audits. We are a public accounting firm registered with the Public Company Accounting Oversight Board (United States) ("PCAOB") and are required to be independent with respect to the Trust in accordance with the U.S. federal securities laws and the applicable rules and regulations of the Securities and Exchange Commission and the PCAOB.

We conducted our audits in accordance with the standards of the PCAOB. Those standards require that we plan and perform the audit to obtain reasonable assurance about whether the financial statements are free of material misstatement, whether due to error or fraud. The Trust is not required to have, nor were we engaged to perform, an audit of the Trust’s internal control over financial reporting. As part of our audits, we are required to obtain an understanding of internal control over financial reporting, but not for the purpose of expressing an opinion on the effectiveness of the Trust’s internal control over financial reporting. Accordingly, we express no such opinion.

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Our audits included performing procedures to assess the risks of material misstatement of the financial statements, whether due to error or fraud, and performing procedures that respond to those risks. Such procedures included examining, on a test basis, evidence regarding the amounts and disclosures in the financial statements. Our procedures included confirmation of securities owned as of December 31, 2023, by correspondence with the custodian, brokers, and others; when replies were not received from brokers and others, we performed other auditing procedures. Our audits also included evaluating the accounting principles used and significant estimates made by management, as well as evaluating the overall presentation of the financial statements. We believe that our audits provide a reasonable basis for our opinion.

We have served as the auditor of one or more investment companies in the Pioneer family of funds since 2017.

Boston, Massachusetts
February 28, 2024

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Additional Information (unaudited)

Qualified interest income is exempt from nonresident alien (NRA) tax withholding. The percentage of the Fund’s ordinary income distributions derived from qualified interest income was 100.00%.

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Approval of Renewal of Investment Management Agreement

Amundi Asset Management US, Inc. (“Amundi US”) serves as the investment adviser to Pioneer AMT-Free Municipal Fund (the “Fund”) pursuant to an investment management agreement between Amundi US and the Fund. In order for Amundi US to remain the investment adviser of the Fund, the Trustees of the Fund, including a majority of the Fund’s Independent Trustees, must determine annually whether to renew the investment management agreement for the Fund.

The contract review process began in January 2023 as the Trustees of the Fund agreed on, among other things, an overall approach and timeline for the process. Contract review materials were provided to the Trustees in March 2023, July 2023 and September 2023. In addition, the Trustees reviewed and discussed the Fund’s performance at regularly scheduled meetings throughout the year, and took into account other information related to the Fund provided to the Trustees at regularly scheduled meetings, in connection with the review of the Fund’s investment management agreement.

In March 2023, the Trustees, among other things, discussed the memorandum provided by Fund counsel that summarized the legal standards and other considerations that are relevant to the Trustees in their deliberations regarding the renewal of the investment management agreement, and reviewed and discussed the qualifications of the investment management teams for the Fund, as well as the level of investment by the Fund’s portfolio managers in the Fund. In July 2023, the Trustees, among other things, reviewed the Fund’s management fees and total expense ratios, the financial statements of Amundi US and its parent companies, profitability analyses provided by Amundi US, and analyses from Amundi US as to possible economies of scale. The Trustees also reviewed the profitability of the institutional business of Amundi US as compared to that of Amundi US’s fund management business, and considered the differences between the fees and expenses of the Fund and the fees and expenses of Amundi US’s institutional accounts, as well as the different services provided by Amundi US to the Fund and to the institutional accounts. The Trustees further considered contract review materials, including additional materials received in response to the Trustees’ request, in September 2023.

At a meeting held on September 19, 2023, based on their evaluation of the information provided by Amundi US and third parties, the Trustees of the Fund, including the Independent Trustees voting separately advised by independent counsel, unanimously approved the renewal of the investment

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management agreement for another year. In approving the renewal of the investment management agreement, the Trustees considered various factors that they determined were relevant, including the factors described below. The Trustees did not identify any single factor as the controlling factor in determining to approve the renewal of the agreement.

Nature, Extent and Quality of Services

The Trustees considered the nature, extent and quality of the services that had been provided by Amundi US to the Fund, taking into account the investment objective and strategy of the Fund. The Trustees also reviewed Amundi US’s investment approach for the Fund and its research process. The Trustees considered the resources of Amundi US and the personnel of Amundi US who provide investment management services to the Fund. They also reviewed the amount of non-Fund assets managed by the portfolio managers of the Fund. They considered the non-investment resources and personnel of Amundi US that are involved in Amundi US’s services to the Fund, including Amundi US’s compliance, risk management, and legal resources and personnel. The Trustees considered the compliance services being provided to the Fund by Amundi US and how Amundi US has addressed any compliance issues during the past year. The Trustees noted the substantial attention and high priority given by Amundi US’s senior management to the Pioneer Fund complex, including with respect to the increasing regulation to which the Pioneer Funds are subject.

The Trustees considered that Amundi US supervises and monitors the performance of the Fund’s service providers and provides the Fund with personnel (including Fund officers) and other resources that are necessary for the Fund’s business management and operations. The Trustees also considered that, as administrator, Amundi US is responsible for the administration of the Fund’s business and other affairs. The Trustees considered that the Fund reimburses Amundi US its pro rata share of Amundi US’s costs of providing administration services to the Pioneer Funds.

Based on these considerations, the Trustees concluded that the nature, extent and quality of services that had been provided by Amundi US to the Fund were satisfactory and consistent with the terms of the investment management agreement.

Performance of the Fund

In considering the Fund’s performance, the Trustees regularly review and discuss throughout the year data prepared by Amundi US and information comparing the Fund’s performance with the performance of its peer group of funds, as classified by Morningstar, Inc. (Morningstar), and with the

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performance of the Fund’s benchmark index. They also discuss the Fund’s performance with Amundi US on a regular basis. The Trustees’ regular reviews and discussions were factored into the Trustees’ deliberations concerning the renewal of the investment management agreement.

Management Fee and Expenses

The Trustees considered information showing the fees and expenses of the Fund in comparison to the management fees of its peer group of funds as classified by Morningstar and also to the expense ratios of a peer group of funds selected on the basis of criteria determined by the Independent Trustees for this purpose using data provided by Strategic Insight Mutual Fund Research and Consulting, LLC (Strategic Insight), an independent third party. The peer group comparisons referred to below are organized in quintiles. Each quintile represents one-fifth of the peer group. In all peer group comparisons referred to below, first quintile is most favorable to the Fund’s shareowners. The Trustees noted that they separately review and consider the impact of the Fund’s transfer agency and Fund- and Amundi US-paid expenses for sub-transfer agency and intermediary arrangements, and that the results of the most recent such review were considered in the consideration of the Fund’s expense ratio.

The Trustees considered that the Fund’s management fee for the most recent fiscal year was in the fourth quintile relative to the management fees paid by other funds in its Morningstar category for the comparable period. The Trustees also considered the breakpoints in the management fee schedule and the reduced fee rates above certain asset levels. The Trustees noted Amundi US’s explanation of the reasons that the Fund’s management fee was in the fourth quintile relative to the management fees paid by other funds in its Morningstar category. The Trustees considered that the expense ratio of the Fund’s Class Y shares for the most recent fiscal year was in the second quintile relative to its Strategic Insight peer group for the comparable period. The Trustees noted that Amundi US had agreed to waive fees and/or reimburse expenses in order to limit the ordinary operating expenses of the Fund.

The Trustees reviewed management fees charged by Amundi US to institutional and other clients, including publicly offered European funds sponsored by Amundi US’s affiliates, unaffiliated U.S. registered investment companies (in a sub-advisory capacity), and unaffiliated foreign and domestic separate accounts. The Trustees also considered Amundi US’s costs in providing services to the Fund and Amundi US’s costs in providing services to the other clients and considered the differences in management fees and profit margins for fund and non-fund services. In evaluating the fees associated with Amundi US’s client accounts, the

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Trustees took into account the respective demands, resources and complexity associated with the Fund and other client accounts. The Trustees noted that, in some instances, the fee rates for those clients were lower than the management fee for the Fund and considered that, under the investment management and administration agreements with the Fund, Amundi US performs additional services for the Fund that it does not provide to those other clients or services that are broader in scope, including oversight of the Fund’s other service providers and activities related to compliance and the extensive regulatory and tax regimes to which the Fund is subject. The Trustees also considered the entrepreneurial risks associated with Amundi US’s management of the Fund.

The Trustees concluded that the management fee payable by the Fund to Amundi US was reasonable in relation to the nature and quality of the services provided by Amundi US.

Profitability

The Trustees considered information provided by Amundi US regarding the profitability of Amundi US with respect to the advisory services provided by Amundi US to the Fund, including the methodology used by Amundi US in allocating certain of its costs to the management of the Fund. The Trustees also considered Amundi US’s profit margin in connection with the overall operation of the Fund. They further reviewed the financial results, including the profit margins, realized by Amundi US from non-fund businesses. The Trustees considered Amundi US’s profit margins in comparison to the limited industry data available and noted that the profitability of any adviser was affected by numerous factors, including its organizational structure and method for allocating expenses. The Trustees concluded that Amundi US’s profitability with respect to the management of the Fund was not unreasonable.

Economies of Scale

The Trustees considered Amundi US’s views relating to economies of scale in connection with the Pioneer Funds as fund assets grow and the extent to which any such economies of scale are shared with the Fund and Fund shareholders. The Trustees noted the breakpoints in the management fee schedule. The Trustees recognize that economies of scale are difficult to identify and quantify, and that, among other factors that may be relevant, are the following: fee levels, expense subsidization, investment by Amundi US in research and analytical capabilities and Amundi US’s commitment and resource allocation to the Fund. The Trustees noted that profitability also may be an indicator of the availability of any economies of scale, although profitability may vary for other reasons including due to

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reductions in expenses. The Trustees concluded that economies of scale, if any, were being appropriately shared with the Fund.

Other Benefits

The Trustees considered the other benefits that Amundi US enjoys from its relationship with the Fund. The Trustees considered the character and amount of fees paid or to be paid by the Fund, other than under the investment management agreement, for services provided by Amundi US and its affiliates. The Trustees further considered the revenues and profitability of Amundi US’s businesses other than the Fund business. To the extent applicable, the Trustees also considered the benefits to the Fund and to Amundi US and its affiliates from the use of “soft” commission dollars generated by the Fund to pay for research and brokerage services.

The Trustees considered that Amundi US is the principal U.S. asset management business of Amundi, which is one of the largest asset managers globally. Amundi’s worldwide asset management business manages over $2.1 trillion in assets (including the Pioneer Funds). The Trustees considered that Amundi US’s relationship with Amundi creates potential opportunities for Amundi US and Amundi that derive from Amundi US’s relationships with the Fund, including Amundi’s ability to market the services of Amundi US globally. The Trustees noted that Amundi US has access to additional research and portfolio management capabilities as a result of its relationship with Amundi and Amundi’s enhanced global presence that may contribute to an increase in the resources available to Amundi US. The Trustees considered that Amundi US and the Fund receive reciprocal intangible benefits from the relationship, including mutual brand recognition and, for the Fund, direct and indirect access to the resources of a large global asset manager. The Trustees concluded that any such benefits received by Amundi US as a result of its relationship with the Fund were reasonable.

Conclusion

After consideration of the factors described above as well as other factors, the Trustees, including the Independent Trustees, concluded that the investment management agreement for the Fund, including the fees payable thereunder, was fair and reasonable and voted to approve the proposed renewal of the investment management agreement.

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Trustees, Officers and Service Providers

Investment Adviser and Administrator
Amundi Asset Management US, Inc.

Custodian and Sub-Administrator
The Bank of New York Mellon Corporation

Independent Registered Public Accounting Firm
Ernst & Young LLP

Principal Underwriter
Amundi Distributor US, Inc.

Legal Counsel
Morgan, Lewis & Bockius LLP

Transfer Agent
BNY Mellon Investment Servicing (US) Inc.

Proxy Voting Policies and Procedures of the Fund are available without charge, upon request, by calling our toll free number (1-800-225-6292). Information regarding how the Fund voted proxies relating to portfolio securities during the most recent 12-month period ended June 30 is publicly available to shareholders at www.amundi.com/us. This information is also available on the Securities and Exchange Commission’s web site at www.sec.gov.

Trustees and Officers

The Fund's Trustees and officers are listed below, together with their principal occupations and other directorships they have held during at least the past five years. Trustees who are interested persons of the Fund within the meaning of the 1940 Act are referred to as Interested Trustees. Trustees who are not interested persons of the Fund are referred to as Independent Trustees. Each of the Trustees serves as a Trustee of each of the 47 U.S. registered investment portfolios for which Amundi US serves as investment adviser (the “Pioneer Funds”). The address for all Trustees and all officers of the Fund is 60 State Street, Boston, Massachusetts 02109.

The Statement of Additional Information of the Fund includes additional information about the Directors and is available, without charge, upon request, by calling 1-800-225-6292.

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Independent Trustees

Name, Age and Position Held With the Trust	Term of Office and Length of Service	Principal Occupation(s) During At Least The Past Five Years	Other Directorships Held by Trustee During At Least The Past Five Years
Thomas J. Perna (72) Chairman of the Board and Trustee	Trustee since 2006. Serves until a successor trustee is elected or earlier retirement or removal.	Private investor (2004 – 2008 and 2013 – present); Chairman (2008 – 2013) and Chief Executive Officer (2008 – 2012), Quadriserv, Inc. (technology products for securities lending industry); and Senior Executive Vice President, The Bank of New York (financial and securities services) (1986 – 2004)	Director, Broadridge Financial Solutions, Inc. (investor communications and securities processing provider for financial services industry) (2009 – present); Director, Quadriserv, Inc. (2005 – 2013); and Commissioner, New Jersey State Civil Service Commission (2011 – 2015)
John E. Baumgardner, Jr. (71)* Trustee	Trustee since 2019. Serves until a successor trustee is elected or earlier retirement or removal.	Of Counsel (2019 – present), Partner (1983-2018), Sullivan & Cromwell LLP (law firm).	Chairman, The Lakeville Journal Company, LLC, (privately-held community newspaper group) (2015-present)
Diane Durnin (65) Trustee	Trustee since 2019. Serves until a successor trustee is elected or earlier retirement or removal.	Managing Director - Head of Product Strategy and Development, BNY Mellon Investment Management (investment management firm) (2012-2018); Vice Chairman – The Dreyfus Corporation (2005 – 2018): Executive Vice President Head of Product, BNY Mellon Investment Management (2007-2012); Executive Director- Product Strategy, Mellon Asset Management (2005-2007); Executive Vice President Head of Products, Marketing and Client Service, Dreyfus Corporation (investment management firm) (2000-2005); Senior Vice President Strategic Product and Business Development, Dreyfus Corporation (1994-2000)	None

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Name, Age and Position Held With the Trust	Term of Office and Length of Service	Principal Occupation(s) During At Least The Past Five Years	Other Directorships Held by Trustee During At Least The Past Five Years
Benjamin M. Friedman (78) Trustee	Trustee since 2008. Serves until a successor trustee is elected or earlier retirement or removal.	William Joseph Maier Professor of Political Economy, Harvard University (1972 – present)	Trustee, Mellon Institutional Funds Investment Trust and Mellon Institutional Funds Master Portfolio (oversaw 17 portfolios in fund complex) (1989 - 2008)
Craig C. MacKay (59) Trustee	Trustee since 2021. Serves until a successor trustee is elected or earlier retirement or removal.	Partner, England & Company, LLC (advisory firm) (2012 – present); Group Head – Leveraged Finance Distribution, Oppenheimer & Company (investment bank) (2006 – 2012); Group Head – Private Finance & High Yield Capital Markets Origination, SunTrust Robinson Humphrey (investment bank) (2003 – 2006); and Founder and Chief Executive Officer, HNY Associates, LLC (investment bank) (1996 – 2003)	Director, Equitable Holdings, Inc. (financial services holding company) (2022 – present); Board Member of Carver Bancorp, Inc. (holding company) and Carver Federal Savings Bank, NA (2017 – present); Advisory Council Member, MasterShares ETF (2016 – 2017); Advisory Council Member, The Deal (financial market information publisher) (2015 – 2016); Board Co-Chairman and Chief Executive Officer, Danis Transportation Company (privately-owned commercial carrier) (2000 – 2003); Board Member and Chief Financial Officer, Customer Access Resources (privately-owned teleservices company) (1998 – 2000); Board Member, Federation of Protestant Welfare Agencies (human services agency) (1993 – present); and Board Treasurer, Harlem Dowling Westside Center (foster care agency) (1999 – 2018)

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Independent Trustees (continued)

Name, Age and Position Held With the Trust	Term of Office and Length of Service	Principal Occupation(s) During At Least The Past Five Years	Other Directorships Held by Trustee During At Least The Past Five Years
Lorraine H. Monchak (66) Trustee	Trustee since 2017. (Advisory Trustee from 2014 - 2017). Serves until a successor trustee is elected or earlier retirement or removal.	Chief Investment Officer, 1199 SEIU Funds (healthcare workers union pension funds) (2001 – present); Vice President – International Investments Group, American International Group, Inc. (insurance company) (1993 – 2001); Vice President – Corporate Finance and Treasury Group, Citibank, N.A. (1980 – 1986 and 1990 – 1993); Vice President – Asset/Liability Management Group, Federal Farm Funding Corporation (government-sponsored issuer of debt securities) (1988 – 1990); Mortgage Strategies Group, Shearson Lehman Hutton, Inc. (investment bank) (1987 – 1988); Mortgage Strategies Group, Drexel Burnham Lambert, Ltd. (investment bank) (1986 – 1987)	None
Marguerite A. Piret (74)** Trustee	Trustee since 2004. Serves until a successor trustee is elected or earlier retirement or removal.	Chief Financial Officer, American Ag Energy, Inc. (controlled environment and agriculture company) (2016 – present); President and Chief Executive Officer, Metric Financial Inc. (formerly known as Newbury Piret Company) (investment banking firm) (1981 – 2019)	Director of New America High Income Fund, Inc. (closed-end investment company) (2004 – present); and Member, Board of Governors, Investment Company Institute (2000 – 2006)

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Name, Age and Position Held With the Trust	Term of Office and Length of Service	Principal Occupation(s) During At Least The Past Five Years	Other Directorships Held by Trustee During At Least The Past Five Years
Fred J. Ricciardi (75) Trustee	Trustee since 2014. Serves until a successor trustee is elected or earlier retirement or removal.	Private investor (2020 – present); Consultant (investment company services) (2012 – 2020); Executive Vice President, BNY Mellon (financial and investment company services) (1969 – 2012); Director, BNY International Financing Corp. (financial services) (2002 – 2012); Director, Mellon Overseas Investment Corp. (financial services) (2009 – 2012); Director, Financial Models (technology) (2005-2007); Director, BNY Hamilton Funds, Ireland (offshore investment companies) (2004-2007); Chairman/Director, AIB/BNY Securities Services, Ltd., Ireland (financial services) (1999-2006); Chairman, BNY Alternative Investment Services, Inc. (financial services) (2005-2007)	None
* Mr. Baumgardner is Of Counsel to Sullivan & Cromwell LLP, which acts as counsel to the Independent Trustees of each Pioneer Fund.
** Ms. Piret became a non-voting Advisory Trustee of the Pioneer Funds effective January 22, 2024.

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Interested Trustees

Name, Age and Position Held With the Trust	Term of Office and Length of Service	Principal Occupation(s) During At Least The Past Five Years	Other Directorships Held by Trustee During At Least The Past Five Years
Lisa M. Jones (60)*** Trustee, President and Chief Executive Officer	Trustee since 2017. Serves until a successor trustee is elected or earlier retirement or removal	Director, CEO and President of Amundi US, Inc. (investment management firm) (since September 2014); Director, CEO and President of Amundi Asset Management US, Inc. (since September 2014); Director, CEO and President of Amundi Distributor US, Inc. (since September 2014); Director, CEO and President of Amundi Asset Management US, Inc. (since September 2014); Chair, Amundi US, Inc., Amundi Distributor US, Inc. and Amundi Asset Management US, Inc. (September 2014 – 2018); Managing Director, Morgan Stanley Investment Management (investment management firm) (2010 – 2013); Director of Institutional Business, CEO of International, Eaton Vance Management (investment management firm) (2005 – 2010); Director of Amundi Holdings US, Inc. (since 2017)	Director of Clearwater Analytics (provider of web-based investment accounting software for reporting and reconciliation services) (September 2022 – present)
Kenneth J. Taubes (64)*,** Trustee	Trustee since 2014. Serves until a successor trustee is elected or earlier retirement or removal	Director and Executive Vice President (since 2008) and Chief Investment Officer, U.S. (since 2010) of Amundi US, Inc. (investment management firm); Director and Executive Vice President and Chief Investment Officer, U.S. of Amundi US (since 2008); Executive Vice President and Chief Investment Officer, U.S. of Amundi Asset Management US, Inc. (since 2009); Portfolio Manager of Amundi US (since 1999); Director of Amundi Holdings US, Inc. (since 2017)	None
*** Ms. Jones and Mr. Taubes are Interested Trustees because they are officers or directors of the Fund’s investment adviser and certain of its affiliates.
**** Mr. Taubes retired as a Trustee, effective January 1, 2024.

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Fund Officers

Name, Age and Position Held With the Fund*****	Term of Office and Length of Service	Principal Occupation(s) During At Least The Past Five Years	Other Directorships Held by Trustee During At Least The Past Five Years
Christopher J. Kelley (58) Secretary and Chief Legal Officer	Since 2004. Serves at the discretion of the Board	Vice President and Associate General Counsel of Amundi US since January 2008; Secretary and Chief Legal Officer of all of the Pioneer Funds since June 2010; Assistant Secretary of all of the Pioneer Funds from September 2003 to May 2010; Vice President and Senior Counsel of Amundi US from July 2002 to December 2007	None
Thomas Reyes (60) Assistant Secretary	Since 2010. Serves at the discretion of the Board	Assistant General Counsel of Amundi US since May 2013 and Assistant Secretary of all the Pioneer Funds since June 2010; Counsel of Amundi US from June 2007 to May 2013	None
Heather L. Melito-Dezan (46) Assistant Secretary	Since 2022. Serves at the discretion of the Board	Director - Trustee and Board Relationships of Amundi US since September 2019; Private practice from 2017 – 2019.	None
Anthony J. Koenig, Jr. (59) Treasurer and Chief Financial and Accounting Officer	Since 2021. Serves at the discretion of the Board	Managing Director, Chief Operations Officer and Fund Treasurer of Amundi US since May 2021; Treasurer of all of the Pioneer Funds since May 2021; Assistant Treasurer of all of the Pioneer Funds from January 2021 to May 2021; and Chief of Staff, US Investment Management of Amundi US from May 2008 to January 2021	None
Luis I. Presutti (57) Assistant Treasurer	Since 2004. Serves at the discretion of the Board	Director – Fund Treasury of Amundi US since 1999; and Assistant Treasurer of all of the Pioneer Funds since 1999	None
Gary Sullivan (64) Assistant Treasurer	Since 2004. Serves at the discretion of the Board	Senior Manager – Fund Treasury of Amundi US since 2012; and Assistant Treasurer of all of the Pioneer Funds since 2002	None
Antonio Furtado (40) Assistant Treasurer	Since 2020. Serves at the discretion of the Board	Fund Oversight Manager – Fund Treasury of Amundi US since 2020; Assistant Treasurer of all of the Pioneer Funds since 2020; and Senior Fund Treasury Analyst from 2012 - 2020	None

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Fund Officers (continued)

Name, Age and Position Held With the Fund*****	Term of Office and Length of Service	Principal Occupation(s) During At Least The Past Five Years	Other Directorships Held by Trustee During At Least The Past Five Years
Michael Melnick (51) Assistant Treasurer	Since 2021. Serves at the discretion of the Board	Vice President - Deputy Fund Treasurer of Amundi US since May 2021; Assistant Treasurer of all of the Pioneer Funds since July 2021; Director of Regulatory Reporting of Amundi US from 2001 – 2021; and Director of Tax of Amundi US from 2000 - 2001	None
John Malone (52) Chief Compliance Officer	Since 2018. Serves at the discretion of the Board	Managing Director, Chief Compliance Officer of Amundi US Asset Management; Amundi Asset Management US, Inc.; and the Pioneer Funds since September 2018; Chief Compliance Officer of Amundi Distributor US, Inc. since January 2014.	None
Brandon Austin (50) Anti-Money Laundering Officer	Since 2022. Serves at the discretion of the Board	Director, Financial Security – Amundi Asset Management; Anti-Money Laundering Officer of all the Pioneer Funds since March 2022: Director of Financial Security of Amundi US since July 2021; Vice President, Head of BSA, AML and OFAC, Deputy Compliance Manager, Crédit Agricole Indosuez Wealth Management (investment management firm) (2013 – 2021)	None
***** Marco Pirondini has been appointed to serve as an Executive Vice President of the Fund and Chief Investment Officer of Amundi US, Inc., effective January 1, 2024.

60Pioneer AMT-Free Municipal Fund | Annual Report | 12/31/23

Table of Contents

How to Contact Amundi

We are pleased to offer a variety of convenient ways for you to contact us for assistance or information.

Call us for:

Account Information, including existing accounts,
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and service forms

1-800-225-6292

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1-800-225-4321

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1-800-622-0176

Write to us:

Amundi
P.O. Box 534427
Pittsburgh, PA 15253-4427

Our toll-free fax	1-800-225-4240
Our internet e-mail address	us.askamundi@amundi.com (for general questions about Amundi only)

Visit our web site: www.amundi.com/us

This report must be preceded or accompanied by a prospectus.

The Fund files a complete schedule of portfolio holdings with the Securities and Exchange Commission for the first and third quarters of each fiscal year as an exhibit to its reports on Form N-PORT. Shareholders may view the filed Form N-PORT by visiting the Commission’s web site at https://www.sec.gov.

Table of Contents

Amundi Asset Management US, Inc.
60 State Street
Boston, MA 02109

www.amundi.com/us

Securities offered through Amundi Distributor US, Inc.
60 State Street, Boston, MA 02109
Underwriter of Pioneer Mutual Funds, Member SIPC
© 2023 Amundi Asset Management US, Inc. 18644-18-0224

ITEM 2. CODE OF ETHICS.

(a) Disclose whether, as of the end of the period covered by the report, the registrant has adopted a code of ethics that applies to the registrant’s principal executive officer, principal financial officer, principal accounting officer or controller, or persons performing similar functions, regardless of whether these individuals are employed by the registrant or a third party. If the registrant has not adopted such a code of ethics, explain why it has not done so.

The registrant has adopted, as of the end of the period covered by this report, a code of ethics that applies to the registrant’s principal executive officer, principal financial officer, principal accounting officer and controller.

(b) For purposes of this Item, the term “code of ethics” means written standards that are reasonably designed to deter wrongdoing and to promote:

(1) Honest and ethical conduct, including the ethical handling of actual or apparent conflicts of interest between personal and professional relationships;

(2) Full, fair, accurate, timely, and understandable disclosure in reports and documents that a registrant files with, or submits to, the Commission and in other public communications made by the registrant;

(3) Compliance with applicable governmental laws, rules, and regulations;

(4) The prompt internal reporting of violations of the code to an appropriate person or persons identified in the code; and

(5) Accountability for adherence to the code.

(c) The registrant must briefly describe the nature of any amendment, during the period covered by the report, to a provision of its code of ethics that applies to the registrant’s principal executive officer, principal financial officer, principal accounting officer or controller, or persons performing similar functions, regardless of whether these individuals are employed by the registrant or a third party, and that relates to any element of the code of ethics definition enumerated in paragraph (b) of this Item. The registrant must file a copy of any such amendment as an exhibit pursuant to Item 10(a), unless the registrant has elected to satisfy paragraph (f) of this Item by posting its code of ethics on its website pursuant to paragraph (f)(2) of this Item, or by undertaking to provide its code of ethics to any person without charge, upon request, pursuant to paragraph (f)(3) of this Item.

The registrant has made no amendments to the code of ethics during the period covered by this report.

(d) If the registrant has, during the period covered by the report, granted a waiver, including an implicit waiver, from a provision of the code of ethics to the registrant’s principal executive officer, principal financial officer, principal accounting officer or controller, or persons performing similar functions, regardless of whether these individuals are employed by the registrant or a third party, that relates to one or more of the items set forth in paragraph (b) of this Item, the registrant must briefly describe the nature of the waiver, the name of the person to whom the waiver was granted, and the date of the waiver.

Not applicable.

(e) If the registrant intends to satisfy the disclosure requirement under paragraph (c) or (d) of this Item regarding an amendment to, or a waiver from, a provision of its code of ethics that applies to the registrant’s principal executive officer, principal financial officer, principal accounting officer or controller, or persons performing similar functions and that relates to any element of the code of ethics definition enumerated in paragraph (b) of this Item by posting such information on its Internet website, disclose the registrant’s Internet address and such intention.

Not applicable.

(f) The registrant must:

(1) File with the Commission, pursuant to Item 12(a)(1), a copy of its code of ethics that applies to the registrant’s principal executive officer, principal financial officer, principal accounting officer or controller, or persons performing similar functions, as an exhibit to its annual report on this Form N-CSR (see attachment);

(2) Post the text of such code of ethics on its Internet website and disclose, in its most recent report on this Form N-CSR, its Internet address and the fact that it has posted such code of ethics on its Internet website; or

(3) Undertake in its most recent report on this Form N-CSR to provide to any person without charge, upon request, a copy of such code of ethics and explain the manner in which such request may be made. See Item 10(2)

ITEM 3. AUDIT COMMITTEE FINANCIAL EXPERT.

(a) (1) Disclose that the registrant’s Board of Trustees has determined that the registrant either:

(i) Has at least one audit committee financial expert serving on its audit committee; or

(ii) Does not have an audit committee financial expert serving on its audit committee.

The registrant’s Board of Trustees has determined that the registrant has at least one audit committee financial expert.

(2) If the registrant provides the disclosure required by paragraph (a)(1)(i) of this Item, it must disclose the name of the audit committee financial expert and whether that person is “independent.” In order to be considered “independent” for purposes of this Item, a member of an audit committee may not, other than in his or her capacity as a member of the audit committee, the Board of Trustees, or any other board committee:

(i) Accept directly or indirectly any consulting, advisory, or other compensatory fee from the issuer; or

(ii) Be an “interested person” of the investment company as defined in Section 2(a)(19) of the Act (15 U.S.C. 80a-2(a)(19)).

Mr. Fred J. Ricciardi, an independent Trustee, is such an audit committee financial expert.

(3) If the registrant provides the disclosure required by paragraph (a)(1) (ii) of this Item, it must explain why it does not have an audit committee financial expert.

Not applicable.

ITEM 4. PRINCIPAL ACCOUNTANT FEES AND SERVICES.

(a) Disclose, under the caption AUDIT FEES, the aggregate fees billed for each of the last two fiscal years for professional services rendered by the principal accountant for the audit of the registrant’s annual financial statements or services that are normally provided by the accountant in connection with statutory and regulatory filings or engagements for those fiscal years.

The audit fees for the Trust were $43,904 payable to Ernst & Young LLP for the year ended December 31, 2023 and $42,215 for the year ended December 31, 2022.

(b) Disclose, under the caption AUDIT-RELATED FEES, the aggregate fees billed in each of the last two fiscal years for assurance and related services by the principal accountant that are reasonably related to the performance of the audit of the registrant’s financial statements and are not reported under paragraph (a) of this Item. Registrants shall describe the nature of the services comprising the fees disclosed under this category.

The audit-related services fees for the Trust were $5,674 payable to Ernst & Young LLP for the year ended December 31, 2023 and $2,408 for the year ended December 31, 2022.

(c) Disclose, under the caption TAX FEES, the aggregate fees billed in each of the last two fiscal years for professional services rendered by the principal accountant for tax compliance, tax advice, and tax planning. Registrants shall describe the nature of the services comprising the fees disclosed under this category.

The Trust paid aggregate non-audit fees to Ernst & Young LLP for tax services of $9,155 and $8,803 during the fiscal years ended December 31, 2023 and 2022, respectively.

(d) Disclose, under the caption ALL OTHER FEES, the aggregate fees billed in each of the last two fiscal years for products and services provided by the principal accountant, other than the services reported in paragraphs (a) through (c) of this Item. Registrants shall describe the nature of the services comprising the fees disclosed under this category.

There were no other fees in 2023 or 2022.

(e) (1) Disclose the audit committee’s pre-approval policies and procedures described in paragraph (c)(7) of Rule 2-01 of Regulation S-X.

PIONEER FUNDS

APPROVAL OF AUDIT, AUDIT-RELATED, TAX AND OTHER SERVICES

PROVIDED BY THE INDEPENDENT AUDITOR

SECTION I - POLICY PURPOSE AND APPLICABILITY

The Pioneer Funds recognize the importance of maintaining the independence of their outside auditors. Maintaining independence is a shared responsibility involving Amundi Asset Management US, Inc., the audit committee and the independent auditors.

The Funds recognize that a Fund’s independent auditors: 1) possess knowledge of the Funds, 2) are able to incorporate certain services into the scope of the audit, thereby avoiding redundant work, cost and disruption of Fund personnel and processes, and 3) have expertise that has value to the Funds. As a result, there are situations where it is desirable to use the Fund’s independent auditors for services in addition to the annual audit and where the potential for conflicts of interests are minimal. Consequently, this policy, which is intended to comply with Rule 210.2-01(C)(7), sets forth guidelines and procedures to be followed by the Funds when retaining the independent audit firm to perform audit, audit-related tax and other services under those circumstances, while also maintaining independence.

Approval of a service in accordance with this policy for a Fund shall also constitute approval for any other Fund whose pre-approval is required pursuant to Rule 210.2-01(c)(7)(ii).

In addition to the procedures set forth in this policy, any non-audit services that may be provided consistently with Rule 210.2-01 may be approved by the Audit Committee itself and any pre-approval that may be waived in accordance with Rule 210.2-01(c)(7)(i)(C) is hereby waived.

Selection of a Fund’s independent auditors and their compensation shall be determined by the Audit Committee and shall not be subject to this policy.


SECTION II - POLICY
SERVICE CATEGORY	SERVICE CATEGORY DESCRIPTION	SPECIFIC PRE-APPROVED SERVICE SUBCATEGORIES
I. AUDIT SERVICES	Services that are directly related to performing the independent audit of the Funds	• Accounting research assistance • SEC consultation, registration statements, and reporting • Tax accrual related matters • Implementation of new accounting standards • Compliance letters (e.g. rating agency letters) • Regulatory reviews and assistance regarding financial matters • Semi-annual reviews (if requested) • Comfort letters for closed end offerings

II. AUDIT-RELATED SERVICES	Services which are not prohibited under Rule 210.2-01(C)(4) (the “Rule”) and are related extensions of the audit services support the audit, or use the knowledge/expertise gained from the audit procedures as a foundation to complete the project. In most cases, if the Audit-Related Services are not performed by the Audit firm, the scope of the Audit Services would likely increase. The Services are typically well-defined and governed by accounting professional standards (AICPA, SEC, etc.)	• AICPA attest and agreed-upon procedures • Technology control assessments • Financial reporting control assessments • Enterprise security architecture assessment


AUDIT COMMITTEE APPROVAL POLICY		AUDIT COMMITTEE REPORTING POLICY

• “One-time” pre-approval for the audit period for all pre-approved specific service subcategories. Approval of the independent auditors as auditors for a Fund shall constitute pre approval for these services. • “One-time” pre-approval for the fund fiscal year within a specified dollar limit for all pre-approved specific service subcategories		• A summary of all such services and related fees reported at each regularly scheduled Audit Committee meeting. • A summary of all such services and related fees (including comparison to specified dollar limits) reported quarterly.

• Specific approval is needed to exceed the pre-approved dollar limit for these services (see general Audit Committee approval policy below for details on obtaining specific approvals)

• Specific approval is needed to use the Fund’s auditors for Audit-Related Services not denoted as “pre-approved”, or to add a specific service subcategory as “pre-approved”

SECTION III - POLICY DETAIL, CONTINUED

SERVICE CATEGORY

DESCRIPTION

SPECIFIC PRE-APPROVED

SERVICE

SUBCATEGORIES

III. TAX SERVICES

Services which are not prohibited by the Rule,

if an officer of the Fund determines that using the Fund’s auditor to provide these services creates significant synergy in the form of efficiency, minimized disruption, or the ability to maintain a desired level of confidentiality.

• Tax planning and support

• Tax controversy assistance

• Tax compliance, tax returns, excise tax returns and support

• Tax opinions

AUDIT COMMITTEE APPROVAL POLICY

AUDIT COMMITTEE REPORTING POLICY

• “One-time” pre-approval for the fund fiscal year within a specified dollar limit

• Specific approval is needed to exceed the pre-approved dollar limits for these services (see general Audit Committee approval policy below for details on obtaining specific approvals)

• Specific approval is needed to use the Fund’s auditors for tax services not denoted as pre-approved, or to add a specific service subcategory as “pre-approved”

• A summary of all such services and related fees (including comparison to specified dollar limits) reported quarterly.

SECTION III - POLICY DETAIL, CONTINUED

SERVICE CATEGORY

DESCRIPTION

SPECIFIC PRE-APPROVED

SERVICE

SUBCATEGORIES

IV. OTHER SERVICES

A. SYNERGISTIC, UNIQUE QUALIFICATIONS

Services which are not prohibited by the Rule, if an officer of the Fund determines that using the Fund’s auditor to provide these services creates significant synergy in the form of efficiency, minimized disruption, the ability to maintain a desired level of confidentiality, or where the Fund’s auditors posses unique or superior qualifications to provide these services, resulting in superior value and results for the Fund.

• Business Risk Management support

• Other control and regulatory compliance projects

AUDIT COMMITTEE APPROVAL POLICY

AUDIT COMMITTEE REPORTING POLICY

• “One-time” pre-approval for the fund fiscal year within a specified dollar limit

• Specific approval is needed to exceed the pre-approved dollar limits for these services (see general Audit Committee approval policy below for details on obtaining specific approvals)

• Specific approval is needed to use the Fund’s auditors for “Synergistic” or “Unique Qualifications” Other Services not denoted as pre-approved to the left, or to add a specific service subcategory as “pre-approved”

• A summary of all such services and related fees (including comparison to specified dollar limits) reported quarterly.

SECTION III - POLICY DETAIL, CONTINUED

SERVICE CATEGORY

DESCRIPTION

SPECIFIC PROHIBITED

SERVICE

SUBCATEGORIES

PROHIBITED SERVICES

Services which result in the auditors losing independence status under the Rule.

1. Bookkeeping or other services related to the accounting records or financial statements of the audit client*

2. Financial information systems design and implementation*

3. Appraisal or valuation services, fairness* opinions, or contribution-in-kind reports

4. Actuarial services (i.e., setting actuarial reserves versus actuarial audit work)*

5. Internal audit outsourcing services*

6. Management functions or human resources

7. Broker or dealer, investment advisor, or investment banking services

8. Legal services and expert services unrelated to the audit

9. Any other service that the Public Company Accounting Oversight Board determines, by regulation, is impermissible


AUDIT COMMITTEE APPROVAL POLICY		AUDIT COMMITTEE REPORTING POLICY
• These services are not to be performed with the exception of the(*) services that may be permitted if they would not be subject to audit procedures at the audit client (as defined in rule 2-01(f)(4)) level the firm providing the service.		• A summary of all services and related fees reported at each regularly scheduled Audit Committee meeting will serve as continual confirmation that has not provided any restricted services.

GENERAL AUDIT COMMITTEE APPROVAL POLICY:

•

For all projects, the officers of the Funds and the Fund’s auditors will each make an assessment to determine that any proposed projects will not impair independence.

•

Potential services will be classified into the four non-restricted service categories and the “Approval of Audit, Audit-Related, Tax and Other Services” Policy above will be applied. Any services outside the specific pre-approved service subcategories set forth above must be specifically approved by the Audit Committee.

•

At least quarterly, the Audit Committee shall review a report summarizing the services by service category, including fees, provided by the Audit firm as set forth in the above policy.

(2) Disclose the percentage of services described in each of paragraphs (b) through (d) of this Item that were approved by the audit committee pursuant to paragraph (c)(7)(i)(C) of Rule 2-01 of Regulation S-X.

Non-Audit Services

Beginning with non-audit service contracts entered into on or after May 6, 2003, the effective date of the

new SEC pre-approval rules, the Trust’s audit committee is required to pre-approve services to

affiliates defined by SEC rules to the extent that the services are determined to have a direct impact on the operations or financial reporting of the Trust. For the years ended December 31, 2023 and 2022, there were no services provided to an affiliate that required the Trust’s audit committee pre-approval.

(f) If greater than 50 percent, disclose the percentage of hours expended on the principal accountants engagement to audit the registrant’s financial statements for the most recent fiscal year that were attributed to work performed by persons other than the principal accountant’s full-time, permanent employees.

N/A

(g) Disclose the aggregate non-audit fees billed by the registrants accountant for services rendered to the registrant, and rendered to the registrants investment adviser (not including any sub-adviser whose role is primarily portfolio management and is subcontracted with or overseen by another investment adviser), and any entity controlling, controlled by, or under common control with the adviser that provides ongoing services to the registrant for each of the last two fiscal years of the registrant.

The Trust paid aggregate non-audit fees to Ernst & Young LLP for tax services of $9,155 and $8,803 during the fiscal years ended December 31, 2023 and 2022, respectively.

(h) Disclose whether the registrants audit committee of the Board of Trustees has considered whether the provision of non-audit services that were rendered to the registrants investment adviser (not including any subadviser whose role is primarily portfolio management and is subcontracted with or overseen by another investment adviser), and any entity controlling, controlled by, or under common control with the investment adviser that provides ongoing services to the registrant that were not pre-approved pursuant to paragraph (c)(7)(ii) of Rule 2-01 of Regulation S-X is compatible with maintaining the principal accountant’s independence.

The Fund’s audit committee of the Board of Trustees has considered whether the provision of non-audit services that were rendered to the Affiliates (as defined) that were not pre- approved pursuant to paragraph (c)(7)(ii) of Rule 2-01 of Regulation S-X is compatible with maintaining the principal accountant’s independence.

(i) A registrant identified by the Commission pursuant to Section 104(i)(2)(A) of the Sarbanes-Oxley Act of 2002 (15 U.S.C. 7214(i)(2)(A)), as having retained, for the preparation of the audit report on its financial statements included in the Form NCSR, a registered public accounting firm that has a branch or office that is located in a foreign jurisdiction and that the Public Company Accounting Oversight Board has determined it is unable to inspect or investigate completely because of a position taken by an authority in the foreign jurisdiction must electronically submit to the Commission on a supplemental basis documentation that establishes that the registrant is not owned or controlled by a governmental entity in the foreign jurisdiction. The registrant must submit this documentation on or before the due date for this form. A registrant that is owned or controlled by a foreign governmental entity is not required to submit such documentation.

N/A

(j) A registrant that is a foreign issuer, as defined in 17 CFR 240.3b-4, identified by the Commission pursuant to Section 104(i)(2)(A) of the Sarbanes-Oxley Act of 2002 (15 U.S.C. 7214(i)(2)(A)), as having retained, for the preparation of the audit report on its financial statements included in the Form N-CSR, a registered public accounting firm that has a branch or office that is located in a foreign jurisdiction and that the Public Company Accounting Oversight Board has determined it is unable to inspect or investigate completely because of a position taken by an authority in the foreign jurisdiction, for each year in which the registrant is so identified, must provide the below disclosures. Also, any such identified foreign issuer that uses a variable-interest entity or any similar structure that results in additional foreign entities being consolidated in the financial statements of the registrant is required to provide the below disclosures for itself and its consolidated foreign operating entity or entities. A registrant must disclose:

(1) That, for the immediately preceding annual financial statement period, a registered public accounting firm that the PCAOB was unable to inspect or investigate completely, because of a position taken by an authority in the foreign jurisdiction, issued an audit report for the registrant;

N/A

(2) The percentage of shares of the registrant owned by governmental entities in the foreign jurisdiction in which the registrant is incorporated or otherwise organized;

N/A

(3) Whether governmental entities in the applicable foreign jurisdiction with respect to that registered public accounting firm have a controlling financial interest with respect to the registrant; N/A

(4) The name of each official of the Chinese Communist Party who is a member of the board of directors of the registrant or the operating entity with respect to the registrant;

N/A

(5) Whether the articles of incorporation of the registrant (or equivalent organizing document) contains any charter of the Chinese Communist Party, including the text of any such charter.

N/A

ITEM 5. AUDIT COMMITTEE OF LISTED REGISTRANTS

(a) If the registrant is a listed issuer as defined in Rule 10A-3 under the Exchange Act (17 CFR 240.10A-3), state whether or not the registrant has a separately-designated standing audit committee established in accordance with Section 3(a)(58)(A) of the Exchange Act (15 U.S.C. 78c(a)(58)(A)). If the registrant has such a committee, however designated, identify each committee member. If the entire board of directors is acting as the registrant’s audit committee as specified in Section 3(a)(58)(B) of the Exchange Act (15 U.S.C. 78c(a)(58)(B)), so state.

N/A

(b) If applicable, provide the disclosure required by Rule 10A-3(d) under the Exchange Act (17 CFR 240.10A-3(d)) regarding an exemption from the listing standards for audit committees.

N/A

ITEM 6. SCHEDULE OF INVESTMENTS.

File Schedule of Investments in securities of unaffiliated issuers as of the close of the reporting period as set forth in 210.1212 of Regulation S-X [17 CFR 210.12-12], unless the schedule is included as part of the report to shareholders filed under Item 1 of this Form.

Included in Item 1

ITEM 7. DISCLOSURE OF PROXY VOTING POLICIES AND PROCEDURES FOR CLOSED-END MANAGEMENT INVESTMENT COMPANIES.

A closed-end management investment company that is filing an annual report on this Form N-CSR must, unless it invests exclusively in non-voting securities, describe the policies and procedures that it uses to determine how to vote proxies relating to portfolio securities, including the procedures that the company uses when a vote presents a conflict between the interests of its shareholders, on the one hand, and those of the company’s investment adviser; principal underwriter; or any affiliated person (as defined in Section 2(a)(3) of the Investment Company Act of 1940 (15 U.S.C. 80a-2(a)(3)) and the rules thereunder) of the company, its investment adviser, or its principal underwriter, on the other. Include any policies and procedures of the company’s investment adviser, or any other third party, that the company uses, or that are used on the company’s behalf, to determine how to vote proxies relating to portfolio securities.

Not applicable to open-end management investment companies.

ITEM 8. PORTFOLIO MANAGERS OF CLOSED-END MANAGEMENT INVESTMENT COMPANIES.

(a) If the registrant is a closed-end management investment company that is filing an annual report on this Form N-CSR, provide the following information:

(1) State the name, title, and length of service of the person or persons employed by or associated with the registrant or an investment adviser of the registrant who are primarily responsible for the day-to-day management of the registrant’s portfolio (“Portfolio Manager”). Also state each Portfolio Manager’s business experience during the past 5 years.

Not applicable to open-end management investment companies.

ITEM 9. PURCHASES OF EQUITY SECURITIES BY CLOSED-END MANAGEMENT INVESTMENT COMPANY AND AFFILIATED PURCHASERS.

(a) If the registrant is a closed-end management investment company, in the following tabular format, provide the information specified in paragraph (b) of this Item with respect to any purchase made by or on behalf of the registrant or any affiliated purchaser, as defined in Rule 10b-18(a)(3) under the Exchange Act (17 CFR 240.10b-18(a)(3)), of shares or other units of any class of the registrant’s equity securities that is registered by the registrant pursuant to Section 12 of the Exchange Act (15 U.S.C. 781).

Not applicable to open-end management investment companies.

ITEM 10. SUBMISSION OF MATTERS TO A VOTE OF SECURITY HOLDERS.

Describe any material changes to the procedures by which shareholders may recommend nominees to the registrant’s board of directors, where those changes were implemented after the registrant last provided disclosure in response to the requirements of Item 407(c)(2)(iv) of Regulation S-R(17 CFR 229.407)(as required by Item 22(b)(15)) of Schedule 14A (17 CFR 240.14a-101), or this Item.

There have been no material changes to the procedures by which the shareholders may recommend nominees to the registrant’s board of directors since the registrant last provided disclosure in response to the requirements of Item 407(c)(2)(iv) of Regulation S-R of Schedule 14(A) in its definitive proxy statement, or this item.

ITEM 11. CONTROLS AND PROCEDURES.

(a) Disclose the conclusions of the registrant’s principal executive and principal financials officers, or persons performing similar functions, regarding the effectiveness of the registrant’s disclosure controls and procedures (as defined in Rule 30a-3(c) under the Act (17 CFR 270.30a-3(c))) as of a date within 90 days of the filing date of the report that includes the disclosure required by this paragraph, based on the evaluation of these controls and procedures required by Rule 30a-3(b) under the Act (17 CFR 270.30(a)-3(b) and Rules 13a-15(b) or 15d-15(b) under the Exchange Act (17 CFR 240.13a-15(b) or 240.15d-15(b)).

The registrant’s principal executive officer and principal financial officer have concluded that the registrant’s disclosure controls and procedures are effective based on the evaluation of these controls and procedures as of a date within 90 days of the filing date of this report.

(b) Disclose any change in the registrant’s internal control over financial reporting (as defined in Rule 30a-3(d) under the Act (17CFR 270.30a-3(d)) that occurred during the period covered by this report that has materially affected, or is reasonably likely to materially affect, the registrant’s internal control over financial reporting.

There were no significant changes in the registrant’s internal control over financial reporting that occurred during the period covered by this report that have materially affected, or are reasonably likely to materially affect, the registrant’s internal control over financial reporting.

Item 12. Disclosure of Securities Lending Activities for Closed-End Management Investment Companies.

(a) If the registrant is a closed-end management investment company, provide the following dollar amounts of income and compensation related to the securities lending activities of the registrant during its most recent fiscal year:

N/A

(1) Gross income from securities lending activities;

N/A

(2) All fees and/or compensation for each of the following securities lending activities and related services: any share of revenue generated by the securities lending program paid to the securities lending agent(s) (revenue split); fees paid for cash collateral management services (including fees deducted from a pooled cash collateral reinvestment vehicle) that are not included in the revenue split; administrative fees that are not included in the revenue split; fees for indemnification that are not included in the revenue split; rebates paid to borrowers; and any other fees relating to the securities lending program that are not included in the revenue split, including a description of those other fees;

N/A

(3) The aggregate fees/compensation disclosed pursuant to paragraph (2); and

N/A

(4) Net income from securities lending activities (i.e., the dollar amount in paragraph (1) minus the dollar amount in paragraph (3)).

If a fee for a service is included in the revenue split, state that the fee is included in the revenue split.

N/A

(b) If the registrant is a closed-end management investment company, describe the services provided to the registrant by the securities lending agent in the registrants most recent fiscal year.

N/A

ITEM 13. EXHIBITS.

(a) File the exhibits listed below as part of this Form. Letter or number the exhibits in the sequence indicated.

(1) Any code of ethics, or amendment thereto, that is the subject of the disclosure required by Item 2, to the extent that the registrant intends to satisfy the Item 2 requirements through filing of an exhibit.

(2) A separate certification for each principal executive officer and principal financial officer of the registrant as required by Rule 30a-2(a) under the Act (17 CFR 270.30a-2(a)) , exactly as set forth below:

Filed herewith.

(b) Certifications pursuant to Rule 30a-2(b) under the 1940 Act and Section 906 of the Sarbanes-Oxley Act of 2002 are attached hereto.

SIGNATURES

[See General Instruction F]

Pursuant to the requirements of the Securities Exchange Act of 1934 and the Investment Company Act of 1940, the registrant has duly caused this report to be signed on its behalf by the undersigned, thereunto duly authorized.

(Registrant) Pioneer Series Trust II

By (Signature and Title)* /s/ Lisa M. Jones

Lisa M. Jones, Principal Executive Officer

Date March 5, 2024

Pursuant to the requirements of the Securities Exchange Act of 1934 and the Investment Company Act of 1940, this report has been signed below by the following persons on behalf of the registrant and in the capacities and on the dates indicated.

By (Signature and Title)* /s/ Lisa M. Jones

Lisa M. Jones, Principal Executive Officer

Date March 5, 2024

By (Signature and Title)* /s/ Anthony J. Koenig, Jr.

Anthony J. Koenig, Jr., Principal Financial Officer

Date March 5, 2024

*	Print the name and title of each signing officer under his or her signature.

Pioneer Series Trust Ii N-CSRCertified annual shareholder report (management investment company)