Eaton Vance Special Investment Trust 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: 811-01545

Eaton Vance Special Investment Trust

(Exact Name of Registrant as Specified in Charter)

Two International Place, Boston, Massachusetts 02110

(Address of Principal Executive Offices)

Deidre E. Walsh

Two International Place, Boston, Massachusetts 02110

(Name and Address of Agent for Services)

(617) 482-8260

(Registrant’s Telephone Number)

October 31

Date of Fiscal Year End

October 31, 2021

Date of Reporting Period

Item 1.

Reports to Stockholders

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Eaton Vance

Short Duration Inflation-Protected Income Fund

Annual Report

October 31, 2021

LOGO

Commodity Futures Trading Commission Registration. The Commodity Futures Trading Commission (“CFTC”) has adopted regulations that subject registered investment companies and advisers to regulation by the CFTC if a fund invests more than a prescribed level of its assets in certain CFTC-regulated instruments (including futures, certain options and swap agreements) or markets itself as providing investment exposure to such instruments. The adviser is registered with the CFTC as a commodity pool operator with respect to its management of the Fund. As the commodity pool operator of the Fund, the adviser has claimed relief under the Commodity Exchange Act from certain reporting and recordkeeping requirements. The adviser is also registered as a commodity trading advisor.

Fund shares are not insured by the FDIC and are not deposits or other obligations of, or guaranteed by, any depository institution. Shares are subject to investment risks, including possible loss of principal invested.

This report must be preceded or accompanied by a current summary prospectus or prospectus. Before investing, investors should consider carefully the investment objective, risks, and charges and expenses of a mutual fund. This and other important information is contained in the summary prospectus and prospectus, which can be obtained from a financial intermediary. Prospective investors should read the prospectus carefully before investing. For further information, please call 1-800-262-1122.

Annual Report October 31, 2021

Eaton Vance

Short Duration Inflation-Protected Income Fund


Table of Contents
Management’s Discussion of Fund Performance			2
Performance			3
Fund Profile			4
Endnotes and Additional Disclosures			5
Fund Expenses			6
Financial Statements			7
Report of Independent Registered Public Accounting Firm			25
Federal Tax Information			26
Liquidity Risk Management Program			27
Management and Organization			28
Privacy Notice			31
Important Notices			33

Eaton Vance

Short Duration Inflation-Protected Income Fund

October 31, 2021

Management’s Discussion of Fund Performance¹

Economic and Market Conditions

During the 12-month period ended October 31, 2021, short-term U.S. Treasury Inflation-Protected Securities (TIPS) returned 6.82%, as measured by the ICE BofA 1-5 Year U.S. Inflation-Linked Treasury Index (the Index).

The period was characterized by a sharp increase in inflation. On a year-over-year basis, the Consumer Price Index (CPI) rose 6.2%, with sizeable price gains across a broad range of goods and services. Gasoline, used cars, and furniture were among those categories registering the largest increases. Core CPI — excluding food and energy prices — rose 4.6% during the period, compared with 1.6% during the previous 12 months. Wage inflation climbed 4.9% year over year, as measured by average hourly earnings.

Inflationary pressures were primarily due to supply-demand imbalances in the economy. Consumer spending was strong during the period, bolstered by government stimulus payments and low borrowing rates. The rollout of COVID-19 vaccines was also very supportive of consumer spending because it unleashed pent-up demand for services as coronavirus-related restrictions eased and people felt more comfortable with social interaction. Meanwhile, global supply-chain disruptions created product shortages, and employers struggled to find workers to fill job openings.

During the first half of the period, the U.S. Federal Reserve (the Fed) largely attributed the rise in inflation to temporary, pandemic-related factors. However, after inflation remained elevated over the summer, the central bank acknowledged that price pressures were lasting longer than originally anticipated. Nonetheless, the Fed maintained its accommodative policies. The central bank held the federal funds rate between 0.00%-0.25% during the period and continued purchasing $120 billion a month in Treasury and mortgage-backed securities.

During the period, rising TIPS breakeven rates — that is, inflation rates expected by the market — suggested that market participants did not expect inflation would be short-lived. Five-year TIPS breakeven rates widened 1.34% during the period, finishing the period at 2.93% — the highest level since the 1997 inception of TIPS. The widening in TIPS breakevens drove a decline in real interest rates — nominal rates adjusted for inflation. Five-year real interest rates fell to all-time lows in May 2021 and then hovered near those levels throughout the remainder of the period. For the period as a whole, five-year real interest rates decreased 0.53%.

Fund Performance

For the 12-month period ended October 31, 2021, Eaton Vance Short Duration Inflation-Protected Income Fund (the Fund) returned 10.23% for Class A shares at net asset value (NAV), outperforming its benchmark, the Index, which returned 6.82%.

The Fund seeks to generate a real return — that is, total return less the estimated cost of inflation — by investing in a combination of “inflation-protected” instruments, including TIPS, and by combining floating-rate bank loans, asset-backed securities (ABS), and commercial mortgage-backed securities (CMBS) with CPI swaps and swaps based on other measures of inflation. Bank loans, ABS, CMBS, CPI swaps, and swaps based on other inflation measures are not represented in the Index.

One of the primary drivers of outperformance relative to the Index was the Fund’s out-of-Index allocation to floating-rate bank loans. Bank loans posted significant gains during a period of generally strong fundamentals among issuers. Furthermore, the low-yield environment fueled investor demand for higher yielding income securities, such as floating-rate bank loans.

TIPS accrued a 5.25% inflation rate during the period. This accrual offset TIPS’ negative real yields and, when combined with the decline in real interest rates, led to strong performance in the Index. The TIPS held by the Fund outperformed the TIPS within the Index, mainly because of more favorable positioning along the yield curve. The Fund’s strategy of swapping nominal interest payments for payments based on changes in the CPI and other measures of inflation also benefited returns versus the Index during the period.

The Fund’s out-of-Index allocation to ABS detracted from performance versus the Index during the period. The low yields on ABS, coupled with tight credit spreads — the yield difference between ABS and U.S. Treasurys of similar maturities — limited performance within the ABS asset class.

As of period-end, the Fund had a 65.6% allocation to TIPS, a 28.4% allocation to floating-rate bank loans, a 4.6% allocation to short-term and other investments, and a 1.4% allocation to ABS. In keeping with the Fund’s principal investment strategy of investing at least 80% of its net assets in “inflation-protected” instruments, interest rate payments on both bank loans and securitized credit, including ABS, were largely swapped for payments based on changes in the CPI and other measures of inflation.

See Endnotes and Additional Disclosures in this report.

Past performance is no guarantee of future results. Returns are historical and are calculated by determining the percentage change in net asset value (NAV) or offering price (as applicable) with all distributions reinvested. Investment return and principal value will fluctuate so that shares, when redeemed, may be worth more or less than their original cost. Performance for periods less than or equal to one year is cumulative. Performance is for the stated time period only; due to market volatility, current Fund performance may be lower or higher than the quoted return. For performance as of the most recent month-end, please refer to eatonvance.com.


		2

Eaton Vance

Short Duration Inflation-Protected Income Fund

October 31, 2021

Performance^2,3

Portfolio Managers Jason C. DesLauriers, CFA and Brian S. Ellis, CFA


% Average Annual Total Returns	Class Inception Date		Performance Inception Date		One Year			Five Years			Ten Years

Class A at NAV		04/01/2010		04/01/2010		10.23	%		3.80	%		2.41	%
Class A with 2.25% Maximum Sales Charge		—		—		7.71			3.32			2.18
Class C at NAV		04/01/2010		04/01/2010		9.46			3.02			1.65
Class C with 1% Maximum Sales Charge		—		—		8.46			3.02			1.65
Class I at NAV		04/01/2010		04/01/2010		10.59			4.06			2.66



ICE BofA 1–5 Year U.S. Inflation-Linked Treasury Index		—		—		6.82	%		3.31	%		1.86	%

% Total Annual Operating Expense Ratios⁴					Class A			Class C			Class I

Gross						1.01	%		1.76	%		0.76	%
Net						0.90			1.65			0.65

Growth of $10,000

This graph shows the change in value of a hypothetical investment of $10,000 in Class A of the Fund for the period indicated. For comparison, the same investment is shown in the indicated index.

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Growth of Investment

Amount Invested

Period Beginning

At NAV

With Maximum Sales Charge

Class C

$10,000

10/31/2011

$11,778

N.A.

Class I

$250,000

10/31/2011

$325,184

N.A.

See Endnotes and Additional Disclosures in this report.


		3

Eaton Vance

Short Duration Inflation-Protected Income Fund

October 31, 2021

Fund Profile

Asset Allocation (% of total investments)⁵

LOGO

See Endnotes and Additional Disclosures in this report.


		4

Eaton Vance

Short Duration Inflation-Protected Income Fund

October 31, 2021

Endnotes and Additional Disclosures

The views expressed in this report are those of the portfolio manager(s) and are current only through the date stated at the top of this page. These views are subject to change at any time based upon market or other conditions, and Eaton Vance and the Fund(s) disclaim any responsibility to update such views. These views may not be relied upon as investment advice and, because investment decisions are based on many factors, may not be relied upon as an indication of trading intent on behalf of any Eaton Vance fund. This commentary may contain statements that are not historical facts, referred to as “forward-looking statements.” The Fund’s actual future results may differ significantly from those stated in any forward-looking statement, depending on factors such as changes in securities or financial markets or general economic conditions, the volume of sales and purchases of Fund shares, the continuation of investment advisory, administrative and service contracts, and other risks discussed from time to time in the Fund’s filings with the Securities and Exchange Commission.

ICE BofA 1-5 Year U.S. Inflation-Linked Treasury Index is an unmanaged index comprised of U.S. Treasury Inflation-Protected Securities with at least $1 billion in outstanding face value and a remaining term to final maturity of at least 1 year and less than 5 years. ICE^® BofA^® indices are not for redistribution or other uses; provided “as is”, without warranties, and with no liability. Eaton Vance has prepared this report and ICE Data Indices, LLC does not endorse it, or guarantee, review, or endorse Eaton Vance’s products. BofA^® is a licensed registered trademark of Bank of America Corporation in the United States and other countries. Unless otherwise stated, index returns do not reflect the effect of any applicable sales charges, commissions, expenses, taxes or leverage, as applicable. It is not possible to invest directly in an index.

Total Returns at NAV do not include applicable sales charges. If sales charges were deducted, the returns would be lower. Total Returns shown with maximum sales charge reflect the stated maximum sales charge. Unless otherwise stated, performance does not reflect the deduction of taxes on Fund distributions or redemptions of Fund shares.

⁴	Source: Fund prospectus. Net expense ratios reflect a contractual expense reimbursement that continues through 2/28/22. Without the reimbursement, performance would have been lower. The expense ratios for the current reporting period can be found in the Financial Highlights section of this report.

⁵	Total investments includes the Fund’s investment in the Portfolio and the Fund’s direct investments in securities and derivatives. Derivative positions are reflected at their unrealized appreciation (depreciation). Other, if any, represents any investment type less than 1% of total investments.

Fund profile subject to change due to active management.

Additional Information

Yield curve is a graphical representation of the yields offered by bonds of various maturities. The yield curve flattens when long-term interest rates fall and/or short-term interest rates increase, and the yield curve steepens when long-term interest rates increase and/or short-term interest rates fall.


		5

Eaton Vance

Short Duration Inflation-Protected Income Fund

October 31, 2021

Fund Expenses

Example: As a Fund shareholder, you incur two types of costs: (1) transaction costs, including sales charges (loads) on purchases and redemption fees (if applicable); and (2) ongoing costs, including management fees; distribution and/or service fees; and other Fund expenses. This Example is intended to help you understand your ongoing costs (in dollars) of Fund investing 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 invested at the beginning of the period and held for the entire period (May 1, 2021 – October 31, 2021).

Actual Expenses: The first section of the table below provides information about actual account values and actual expenses. You may use the information in this section, together with the amount you invested, to estimate the expenses that you paid over the period. Simply divide your account value by $1,000 (for example, an $8,600 account value divided by $1,000 = 8.6), then multiply the result by the number in the first section under the heading entitled “Expenses Paid During Period” to estimate the expenses you paid on your account during this period.

Hypothetical Example for Comparison Purposes: The second section of the table below provides information about hypothetical account values and hypothetical expenses based on the actual Fund expense ratio and an assumed rate of return of 5% per year (before expenses), which is not the actual Fund 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 your 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 table are meant to highlight your ongoing costs only and do not reflect any transactional costs, such as sales charges (loads) or redemption fees (if applicable). Therefore, the second section of the table 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 transactional costs were included, your costs would be higher.


	Beginning Account Value (5/1/21)		Ending Account Value (10/31/21)		Expenses Paid During Period* (5/1/21 – 10/31/21)			Annualized Expense Ratio

Actual
Class A	$	1,000.00	$	1,038.40	$	4.26	**		0.83	%
Class C	$	1,000.00	$	1,034.60	$	8.10	**		1.58	%
Class I	$	1,000.00	$	1,039.50	$	2.98	**		0.58	%

Hypothetical
(5% return per year before expenses)
Class A	$	1,000.00	$	1,021.02	$	4.23	**		0.83	%
Class C	$	1,000.00	$	1,017.29	$	8.03	**		1.58	%
Class I	$	1,000.00	$	1,022.28	$	2.96	**		0.58	%

Expenses are equal to the Fund’s annualized expense ratio for the indicated Class, multiplied by the average account value over the period, multiplied by 184/365 (to reflect the one-half year period). The Example assumes that the $1,000 was invested at the net asset value per share determined at the close of business on April 30, 2021. The Example reflects the expenses of both the Fund and the Portfolio.

**	Absent an allocation of certain expenses to an affiliate, expenses would be higher.


		6

Eaton Vance

Short Duration Inflation-Protected Income Fund

October 31, 2021

Portfolio of Investments


Investment in Affiliated Portfolio — 28.5%
Description			Value

Senior Debt Portfolio (identified cost, $116,664,195)			$	118,849,044

Total Investment in Affiliated Portfolio (identified cost $116,664,195)			$	118,849,044

Asset-Backed Securities — 1.5%
Security	Principal Amount (000’s omitted)		Value

ARI Fleet Lease Trust, Series 2018-B, Class A2, 3.22%, 8/16/27⁽¹⁾	$	17	$	17,147

Coinstar Funding, LLC, Series 2017-1A, Class A2, 5.216%, 4/25/47⁽¹⁾		1,357		1,357,270

Foundation Finance Trust, Series 2017-1A, Class A, 3.30%, 7/15/33⁽¹⁾		219		221,284

FREED ABS Trust, Series 2020-FP1, Class A, 2.52%, 3/18/27⁽¹⁾		38		38,018

LL ABS Trust, Series 2020-1A, Class A, 2.33%, 1/17/28⁽¹⁾		253		254,490

Marlette Funding Trust, Series 2020-2A, Class B, 1.83%, 9/16/30⁽¹⁾		393		394,823

MVW, LLC, Series 2020-1A, Class A, 1.74%, 10/20/37⁽¹⁾		83		83,474

Small Business Lending Trust, Series 2020-A, Class A, 2.62%, 12/15/26⁽¹⁾		107		107,710

SpringCastle America Funding, LLC, Series 2020-AA, Class A, 1.97%, 9/25/37⁽¹⁾		1,152		1,155,330

Stack Infrastructure Issuer, LLC, Series 2019-1A, Class A2, 4.54%, 2/25/44⁽¹⁾		968		1,011,436

Tesla Auto Lease Trust:

Series 2020-A, Class A3, 0.68%, 12/20/23⁽¹⁾		164		164,423

Series 2020-A, Class A4, 0.78%, 12/20/23⁽¹⁾		104		104,279

Theorem Funding Trust, Series 2020-1A, Class A, 2.48%, 10/15/26⁽¹⁾		81		80,943

Vantage Data Centers, LLC, Series 2020-2A, Class A2, 1.992%, 9/15/45⁽¹⁾		1,105		1,090,402

Total Asset-Backed Securities (identified cost $6,138,513)			$	6,081,029

Commercial Mortgage-Backed Securities — 0.4%
Security	Principal Amount (000’s omitted)		Value

COMM Mortgage Trust:

Series 2013-CR11, Class D, 5.284%, 8/10/50⁽¹⁾⁽²⁾	$	455	$	452,785

Series 2015-CR22, Class D, 4.243%, 3/10/48⁽¹⁾⁽²⁾		1,000		1,003,106


Security	Principal Amount (000’s omitted)		Value

JPMorgan Chase Commercial Mortgage Securities Trust, Series 2011-C5, Class D, 5.566%, 8/15/46⁽¹⁾⁽²⁾	$	342	$	340,633

Total Commercial Mortgage-Backed Securities (identified cost $1,843,606)			$	1,796,524

U.S. Treasury Obligations — 66.0%
Security	Principal Amount (000’s omitted)		Value

U.S. Treasury Inflation-Protected Bonds:

2.00%, 1/15/26⁽³⁾	$	13,783	$	16,120,033

2.375%, 1/15/25⁽³⁾		15,963		18,372,941

U.S. Treasury Inflation-Protected Notes:

0.125%, 1/15/23⁽³⁾		13,036		13,538,179

0.125%, 7/15/24⁽³⁾		12,673		13,590,150

0.125%, 10/15/24⁽³⁾		15,993		17,188,857

0.125%, 4/15/25⁽³⁾		16,944		18,265,362

0.125%, 10/15/25⁽³⁾		16,868		18,335,177

0.125%, 4/15/26⁽³⁾		15,646		17,040,275

0.125%, 7/15/26⁽³⁾		16,548		18,138,278

0.25%, 1/15/25⁽³⁾		18,479		19,941,250

0.375%, 7/15/23⁽³⁾		14,105		14,929,506

0.375%, 7/15/25⁽³⁾		11,535		12,639,804

0.50%, 4/15/24⁽³⁾		16,269		17,452,340

0.625%, 4/15/23⁽³⁾		16,519		17,373,202

0.625%, 1/15/24⁽³⁾		18,758		20,085,204

0.625%, 1/15/26⁽³⁾		19,571		21,689,105

Total U.S. Treasury Obligations (identified cost $269,284,492)			$	274,699,663

Short-Term Investments — 2.3%
Description	Units		Value

Eaton Vance Cash Reserves Fund, LLC, 0.09%⁽⁴⁾		9,713,035	$	9,713,035

Total Short-Term Investments (identified cost $9,713,035)			$	9,713,035

Total Investments — 98.7% (identified cost $403,643,841)			$	411,139,295

Other Assets, Less Liabilities — 1.3%			$	5,231,781

Net Assets — 100.0%			$	416,371,076

The percentage shown for each investment category in the Portfolio of Investments is based on net assets.


		7		See Notes to Financial Statements.

Eaton Vance

Short Duration Inflation-Protected Income Fund

October 31, 2021

Portfolio of Investments — continued

⁽¹⁾

Security exempt from registration under Rule 144A of the Securities Act of 1933, as amended. These securities may be sold in certain transactions in reliance on an exemption from registration (normally to qualified institutional buyers). At October 31, 2021, the aggregate value of these securities is $7,877,553 or 1.9% of the Fund’s net assets.

⁽²⁾	Weighted average fixed-rate coupon that changes/updates monthly. Rate shown is the rate at October 31, 2021.

⁽³⁾	Inflation-linked security whose principal is adjusted for inflation based on changes in the U.S. Consumer Price Index. Interest is calculated based on the inflation-adjusted principal.

⁽⁴⁾	Affiliated investment company, available to Eaton Vance portfolios and funds, which invests in high quality, U.S. dollar denominated money market instruments. The rate shown is the annualized seven-day yield as of October 31, 2021.

Centrally Cleared Inflation Swaps

Notional
Amount
(000’s omitted)

Fund
Pays/Receives
Return on
Reference Index

Reference Index

Fund
Pays/Receives
Rate

Annual
Rate

Termination
Date

Value/Unrealized
Appreciation
(Depreciation)

USD

7,000

Receives

Return on CPI-U (NSA)
(pays upon termination)

Pays

2.335%
(pays upon termination)

3/2/25

430,777

USD

5,000

Receives

Return on CPI-U (NSA)
(pays upon termination)

Pays

1.404%
(pays upon termination)

3/6/25

503,708

USD

4,000

Receives

Return on CPI-U (NSA)
(pays upon termination)

Pays

0.655%
(pays upon termination)

3/27/25

555,095

USD

6,000

Receives

Return on CPI-U (NSA)
(pays upon termination)

Pays

1.915%
(pays upon termination)

9/2/25

569,069

USD

4,000

Receives

Return on CPI-U (NSA)
(pays upon termination)

Pays

0.454%
(pays upon termination)

3/24/26

690,737

USD

10,000

Receives

Return on CPI-U (NSA)
(pays upon termination)

Pays

2.729%
(pays upon termination)

5/27/26

416,427

USD

10,000

Receives

Return on CPI-U (NSA)
(pays upon termination)

Pays

2.705%
(pays upon termination)

8/11/26

286,219

USD

5,000

Receives

Return on CPI-U (NSA)
(pays upon termination)

Pays

1.901%
(pays upon termination)

9/1/26

525,641

USD

15,000

Receives

Return on CPI-U (NSA)
(pays upon termination)

Pays

3.164%
(pays upon termination)

10/28/26

(81,540

)

USD

10,000

Receives

Return on CPI-U (NSA)
(pays upon termination)

Pays

2.545%
(pays upon termination)

4/19/27

552,000

USD

10,000

Receives

Return on CPI-U (NSA)
(pays upon termination)

Pays

2.81%
(pays upon termination)

10/12/27

110,147

4,558,280


		8		See Notes to Financial Statements.

Eaton Vance

Short Duration Inflation-Protected Income Fund

October 31, 2021

Portfolio of Investments — continued

Inflation Swaps

Counterparty

Notional
Amount
(000’s omitted)

Fund
Pays/Receives
Return on
Reference Index

Reference Index

Fund
Pays/Receives
Rate

Annual
Rate

Termination
Date

Value/
Unrealized
Appreciation

Bank of America, N.A.

5,000

Receives

Return on CPI-U (NSA)
(pays upon termination)

Pays

1.784%
(pays upon termination)

6/19/22

288,448

Bank of America, N.A.

5,000

Receives

Return on CPI-U (NSA)
(pays upon termination)

Pays

1.770%
(pays upon termination)

6/22/22

291,403

Bank of America, N.A.

8,000

Receives

Return on CPI-U (NSA)
(pays upon termination)

Pays

1.856%
(pays upon termination)

1/9/24

522,519

Barclays Bank PLC

6,000

Receives

Return on CPI-U (NSA)
(pays upon termination)

Pays

1.934%
(pays upon termination)

7/20/22

300,042

Barclays Bank PLC

10,000

Receives

Return on CPI-U (NSA)
(pays upon termination)

Pays

2.157%
(pays upon termination)

1/9/23

421,158

Citibank, N.A.

5,000

Receives

Return on CPI-U (NSA)
(pays upon termination)

Pays

2.207%
(pays upon termination)

1/23/23

196,275

Citibank, N.A.

5,000

Receives

Return on CPI-U (NSA)
(pays upon termination)

Pays

1.763%
(pays upon termination)

1/2/24

347,529

Goldman Sachs International

7,000

Receives

Return on CPI-U (NSA)
(pays upon termination)

Pays

1.890%
(pays upon termination)

12/21/23

464,514

Goldman Sachs International

6,000

Receives

Return on CPI-U (NSA)
(pays upon termination)

Pays

1.783%
(pays upon termination)

12/28/23

422,531

3,254,419

Abbreviations:



CPI-U (NSA)	–	Consumer Price Index All Urban Non-Seasonally Adjusted

Currency Abbreviations:



USD	–	United States Dollar


		9		See Notes to Financial Statements.

Eaton Vance

Short Duration Inflation-Protected Income Fund

October 31, 2021

Statement of Assets and Liabilities


Assets	October 31, 2021

Investment in affiliated Portfolio, at value (identified cost, $116,664,195)	$	118,849,044

Unaffiliated investments, at value (identified cost, $277,266,611)		282,577,216

Affiliated investment, at value (identified cost, $9,713,035)		9,713,035

Cash		7

Deposits for derivatives collateral —

Centrally cleared swap contracts		3,027,424

OTC swap contracts		3,000,000

Interest receivable		346,648

Dividends receivable from affiliated investment		168

Receivable for Fund shares sold		5,039,451

Receivable for open swap contracts		3,254,419

Receivable from affiliate		55,634

Total assets	$	425,863,046

Liabilities

Cash collateral due to brokers	$	3,000,000

Payable for investments purchased		5,611,846

Payable for Fund shares redeemed		431,799

Payable for variation margin on open centrally cleared swap contracts		192,957

Payable to affiliates:

Investment adviser fee		104,705

Distribution and service fees		20,754

Trustees’ fees		42

Accrued expenses		129,867

Total liabilities	$	9,491,970

Net Assets	$	416,371,076

Sources of Net Assets

Paid-in capital	$	413,272,895

Distributable earnings		3,098,181

Total	$	416,371,076

Class A Shares

Net Assets	$	58,834,912

Shares Outstanding		5,606,009

Net Asset Value and Redemption Price Per Share

(net assets ÷ shares of beneficial interest outstanding)	$	10.49

Maximum Offering Price Per Share

(100 ÷ 97.75 of net asset value per share)	$	10.73

Class C Shares

Net Assets	$	11,321,963

Shares Outstanding		1,089,548

Net Asset Value and Offering Price Per Share*

(net assets ÷ shares of beneficial interest outstanding)	$	10.39

Class I Shares

Net Assets	$	346,214,201

Shares Outstanding		32,965,198

Net Asset Value, Offering Price and Redemption Price Per Share

(net assets ÷ shares of beneficial interest outstanding)	$	10.50

On sales of $100,000 or more, the offering price of Class A shares is reduced.

*	Redemption price per share is equal to the net asset value less any applicable contingent deferred sales charge.


		10		See Notes to Financial Statements.

Eaton Vance

Short Duration Inflation-Protected Income Fund

October 31, 2021

Statement of Operations


Investment Income	Year Ended October 31, 2021

Interest	$	8,118,720

Interest and other income allocated from affiliated Portfolio		3,828,284

Dividends from affiliated investment		3,156

Dividends allocated from affiliated Portfolio (net of foreign taxes, $1,249)		45,338

Expenses, excluding interest expense and fees, allocated from affiliated Portfolio		(406,278	)

Interest expense and fees allocated from affiliated Portfolio		(241,400	)

Total investment income	$	11,347,820

Expenses

Investment adviser fee	$	846,124

Distribution and service fees

Class A		104,099

Class C		62,223

Trustees’ fees and expenses		500

Custodian fee		45,127

Transfer and dividend disbursing agent fees		130,222

Legal and accounting services		55,965

Printing and postage		20,318

Registration fees		96,968

Miscellaneous		15,397

Total expenses	$	1,376,943

Deduct —

Reimbursement of expenses by affiliate	$	275,971

Total expense reductions	$	275,971

Net expenses	$	1,100,972

Net investment income	$	10,246,848

Realized and Unrealized Gain (Loss)

Net realized gain (loss) —

Investment transactions	$	840,930

Investment transactions — affiliated investment		52

Swap contracts		(5,008	)

Net realized gain (loss) allocated from affiliated Portfolio —

Investment transactions		(276,894	)

Foreign currency transactions		30,435

Forward foreign currency exchange contracts		269,640

Net realized gain	$	859,155

Change in unrealized appreciation (depreciation) —

Investments	$	2,902,134

Swap contracts		8,210,829

Change in unrealized appreciation (depreciation) allocated from affiliated Portfolio —

Investments		2,431,106

Foreign currency		9,466

Forward foreign currency exchange contracts		76,677

Net change in unrealized appreciation (depreciation)	$	13,630,212

Net realized and unrealized gain	$	14,489,367

Net increase in net assets from operations	$	24,736,215


		11		See Notes to Financial Statements.

Eaton Vance

Short Duration Inflation-Protected Income Fund

October 31, 2021

Statements of Changes in Net Assets


	Year Ended October 31,
Increase (Decrease) in Net Assets	2021			2020

From operations —

Net investment income	$	10,246,848		$	4,557,380

Net realized gain (loss)		859,155			(5,246,790	)

Net change in unrealized appreciation (depreciation)		13,630,212			4,640,547

Net increase in net assets from operations	$	24,736,215		$	3,951,137

Distributions to shareholders —

Class A	$	(1,528,395	)	$	(619,619	)

Class C		(203,009	)		(89,193	)

Class I		(8,833,344	)		(3,862,054	)

Total distributions to shareholders	$	(10,564,748	)	$	(4,570,866	)

Transactions in shares of beneficial interest —

Proceeds from sale of shares

Class A	$	40,295,900		$	11,394,245

Class C		7,820,191			495,004

Class I		272,611,215			76,557,628

Net asset value of shares issued to shareholders in payment of distributions declared

Class A		1,499,890			603,591

Class C		202,273			89,064

Class I		8,791,040			3,829,656

Cost of shares redeemed

Class A		(15,222,497	)		(13,133,462	)

Class C		(1,019,751	)		(2,386,210	)

Class I		(93,584,235	)		(132,494,195	)

Net asset value of shares converted

Class A		1,150,901			214,597

Class C		(1,150,901	)		(214,597	)

Net increase (decrease) in net assets from Fund share transactions	$	221,394,026		$	(55,044,679	)

Net increase (decrease) in net assets	$	235,565,493		$	(55,664,408	)

Net Assets

At beginning of year	$	180,805,583		$	236,469,991

At end of year	$	416,371,076		$	180,805,583


		12		See Notes to Financial Statements.

Eaton Vance

Short Duration Inflation-Protected Income Fund

October 31, 2021

Financial Highlights


	Class A

	Year Ended October 31,
	2021			2020			2019			2018			2017

Net asset value — Beginning of year	$	9.850		$	9.730		$	9.720		$	9.860		$	9.820

Income (Loss) From Operations

Net investment income⁽¹⁾	$	0.366		$	0.209		$	0.240		$	0.254		$	0.176

Net realized and unrealized gain (loss)		0.630			0.120	⁽²⁾		(0.008	)		(0.142	)		0.022

Total income from operations	$	0.996		$	0.329		$	0.232		$	0.112		$	0.198

Less Distributions

From net investment income	$	(0.356	)	$	(0.209	)	$	(0.222	)	$	(0.252	)	$	(0.158	)

Total distributions	$	(0.356	)	$	(0.209	)	$	(0.222	)	$	(0.252	)	$	(0.158	)

Net asset value — End of year	$	10.490		$	9.850		$	9.730		$	9.720		$	9.860

Total Return⁽³⁾⁽⁴⁾		10.23	%		3.46	%		2.41	%		1.14	%		2.03	%

Ratios/Supplemental Data

Net assets, end of year (000’s omitted)	$	58,835		$	28,768		$	29,350		$	37,919		$	20,314

Ratios (as a percentage of average daily net assets):⁽⁵⁾

Expenses⁽⁴⁾⁽⁶⁾		0.84	%		0.90	%		0.95	%		0.87	%		0.86	%

Net investment income		3.54	%		2.16	%		2.46	%		2.59	%		1.78	%

Portfolio Turnover of the Fund⁽⁷⁾		25	%		68	%		36	%		51	%		40	%

⁽¹⁾	Computed using average shares outstanding.

⁽²⁾	The per share amount is not in accord with the net realized and unrealized gain (loss) for the period because of the timing of Fund share transactions and the amount of the per share realized and unrealized gains and losses at such time.

⁽³⁾	Returns are historical and are calculated by determining the percentage change in net asset value with all distributions reinvested and do not reflect the effect of sales charges.

⁽⁴⁾	The investment adviser and the administrator of the Fund reimbursed expenses (equal to 0.10%, 0.11%, 0.14%, 0.11% and 0.13% of average daily net assets for the years ended October 31, 2021, 2020, 2019, 2018 and 2017, respectively). Absent this reimbursement, total return would be lower.

⁽⁵⁾	Includes the Fund’s share of the Portfolio’s allocated expenses.

⁽⁶⁾	Includes interest expense, including allocated from the Portfolio, of 0.09%, 0.15%, 0.20%, 0.12% and 0.09% of average daily net assets for the years ended October 31, 2021, 2020, 2019, 2018 and 2017, respectively.

⁽⁷⁾	Percentage includes both the Fund’s contributions to and withdrawals from the Portfolio and purchases and sales of securities held directly by the Fund.


		13		See Notes to Financial Statements.

Eaton Vance

Short Duration Inflation-Protected Income Fund

October 31, 2021

Financial Highlights — continued


	Class C

	Year Ended October 31,
	2021			2020			2019			2018			2017

Net asset value — Beginning of year	$	9.760		$	9.660		$	9.660		$	9.810		$	9.780

Income (Loss) From Operations

Net investment income⁽¹⁾	$	0.283		$	0.134		$	0.163		$	0.179		$	0.103

Net realized and unrealized gain (loss)		0.632			0.116	⁽²⁾		(0.002	)		(0.148	)		0.020

Total income from operations	$	0.915		$	0.250		$	0.161		$	0.031		$	0.123

Less Distributions

From net investment income	$	(0.285	)	$	(0.150	)	$	(0.161	)	$	(0.181	)	$	(0.093	)

Total distributions	$	(0.285	)	$	(0.150	)	$	(0.161	)	$	(0.181	)	$	(0.093	)

Net asset value — End of year	$	10.390		$	9.760		$	9.660		$	9.660		$	9.810

Total Return⁽³⁾⁽⁴⁾		9.46	%		2.74	%		1.58	%		0.31	%		1.26	%

Ratios/Supplemental Data

Net assets, end of year (000’s omitted)	$	11,322		$	5,152		$	7,118		$	13,528		$	9,723

Ratios (as a percentage of average daily net assets):⁽⁵⁾

Expenses⁽⁴⁾⁽⁶⁾		1.59	%		1.65	%		1.70	%		1.62	%		1.61	%

Net investment income		2.76	%		1.40	%		1.68	%		1.83	%		1.05	%

Portfolio Turnover of the Fund⁽⁷⁾		25	%		68	%		36	%		51	%		40	%

⁽¹⁾	Computed using average shares outstanding.

⁽²⁾	The per share amount is not in accord with the net realized and unrealized gain (loss) for the period because of the timing of Fund share transactions and the amount of the per share realized and unrealized gains and losses at such time.

⁽³⁾	Returns are historical and are calculated by determining the percentage change in net asset value with all distributions reinvested and do not reflect the effect of sales charges.

⁽⁴⁾	The investment adviser and the administrator of the Fund reimbursed expenses (equal to 0.10%, 0.11%, 0.14%, 0.11% and 0.13% of average daily net assets for the years ended October 31, 2021, 2020, 2019, 2018 and 2017, respectively). Absent this reimbursement, total return would be lower.

⁽⁵⁾	Includes the Fund’s share of the Portfolio’s allocated expenses.

⁽⁶⁾	Includes interest expense, including allocated from the Portfolio, of 0.09%, 0.15%, 0.20%, 0.12% and 0.09% of average daily net assets for the years ended October 31, 2021, 2020, 2019, 2018 and 2017, respectively.

⁽⁷⁾	Percentage includes both the Fund’s contributions to and withdrawals from the Portfolio and purchases and sales of securities held directly by the Fund.


		14		See Notes to Financial Statements.

Eaton Vance

Short Duration Inflation-Protected Income Fund

October 31, 2021

Financial Highlights — continued


	Class I

	Year Ended October 31,
	2021			2020			2019			2018			2017

Net asset value — Beginning of year	$	9.850		$	9.730		$	9.710		$	9.850		$	9.810

Income (Loss) From Operations

Net investment income⁽¹⁾	$	0.401		$	0.234		$	0.265		$	0.282		$	0.205

Net realized and unrealized gain (loss)		0.629			0.114	⁽²⁾		(0.005	)		(0.147	)		0.014

Total income from operations	$	1.030		$	0.348		$	0.260		$	0.135		$	0.219

Less Distributions

From net investment income	$	(0.380	)	$	(0.228	)	$	(0.240	)	$	(0.275	)	$	(0.179	)

Total distributions	$	(0.380	)	$	(0.228	)	$	(0.240	)	$	(0.275	)	$	(0.179	)

Net asset value — End of year	$	10.500		$	9.850		$	9.730		$	9.710		$	9.850

Total Return⁽³⁾⁽⁴⁾		10.59	%		3.66	%		2.71	%		1.37	%		2.25	%

Ratios/Supplemental Data

Net assets, end of year (000’s omitted)	$	346,214		$	146,885		$	200,002		$	273,458		$	164,940

Ratios (as a percentage of average daily net assets):⁽⁵⁾

Expenses⁽⁴⁾⁽⁶⁾		0.59	%		0.65	%		0.70	%		0.62	%		0.60	%

Net investment income		3.88	%		2.42	%		2.72	%		2.87	%		2.08	%

Portfolio Turnover of the Fund⁽⁷⁾		25	%		68	%		36	%		51	%		40	%

⁽¹⁾	Computed using average shares outstanding.

⁽²⁾	The per share amount is not in accord with the net realized and unrealized gain (loss) for the period because of the timing of Fund share transactions and the amount of the per share realized and unrealized gains and losses at such time.

⁽³⁾	Returns are historical and are calculated by determining the percentage change in net asset value with all distributions reinvested.

⁽⁴⁾	The investment adviser and the administrator of the Fund reimbursed expenses (equal to 0.10%, 0.11%, 0.14%, 0.11% and 0.13% of average daily net assets for the years ended October 31, 2021, 2020, 2019, 2018 and 2017, respectively). Absent this reimbursement, total return would be lower.

⁽⁵⁾	Includes the Fund’s share of the Portfolio’s allocated expenses.

⁽⁶⁾	Includes interest expense, including allocated from the Portfolio, of 0.09%, 0.15%, 0.20%, 0.12% and 0.09% of average daily net assets for the years ended October 31, 2021, 2020, 2019, 2018 and 2017, respectively.

⁽⁷⁾	Percentage includes both the Fund’s contributions to and withdrawals from the Portfolio and purchases and sales of securities held directly by the Fund.


		15		See Notes to Financial Statements.

Eaton Vance

Short Duration Inflation-Protected Income Fund

October 31, 2021

Notes to Financial Statements

1 Significant Accounting Policies

Eaton Vance Short Duration Inflation-Protected Income Fund (the Fund) is a non-diversified series of Eaton Vance Special Investment Trust (the Trust). The Trust is a Massachusetts business trust registered under the Investment Company Act of 1940, as amended (the 1940 Act), as an open-end management investment company. The Fund offers three classes of shares. Class A shares are generally sold subject to a sales charge imposed at time of purchase. Class C shares are sold at net asset value and are generally subject to a contingent deferred sales charge (see Note 5). Effective January 25, 2019, Class C shares generally automatically convert to Class A shares ten years after their purchase and, effective November 5, 2020, automatically convert to Class A shares eight years after their purchase as described in the Fund’s prospectus. Class I shares are sold at net asset value and are not subject to a sales charge. Each class represents a pro-rata interest in the Fund, but votes separately on class-specific matters and (as noted below) is subject to different expenses. Realized and unrealized gains and losses and net investment income and losses, other than class-specific expenses, are allocated daily to each class of shares based on the relative net assets of each class to the total net assets of the Fund. Each class of shares differs in its distribution plan and certain other class-specific expenses. The Fund’s investment objective is real return (real return is defined as total return less the estimated cost of inflation (typically measured by the change in an official inflation measure)). The Fund pursues its investment objective by investing in inflation protected instruments, including Treasury Inflation Protected Securities, and other fixed or floating-rate debt obligations with respect to which the Fund enters into agreements to swap nominal interest payments for payments based on changes in the U.S. Consumer Price Index or other measure of inflation. The Fund may also invest in certain registered investment companies sponsored by the Eaton Vance organization. During the year ended October 31, 2021, the Fund held interests in Senior Debt Portfolio (the Portfolio), a Massachusetts business trust managed by Boston Management and Research (BMR). The value of the Fund’s investment in the Portfolio reflects the Fund’s proportionate interest in the net assets of the Portfolio (1.4% at October 31, 2021). The performance of the Fund is directly affected by the performance of the Portfolio. A copy of the Portfolio’s financial statements is available by calling Eaton Vance at 1-800-262-1122 or on the EDGAR database on the Securities and Exchange Commission’s website at www.sec.gov.

The following is a summary of significant accounting policies of the Fund. The policies are in conformity with accounting principles generally accepted in the United States of America (U.S. GAAP). The Fund is an investment company and follows accounting and reporting guidance in the Financial Accounting Standards Board (FASB) Accounting Standards Codification Topic 946.

A Investment Valuation — The following methodologies are used to determine the market value or fair value of investments. The valuation policy of the Fund and of the Portfolio is as follows:

Debt Obligations. Debt obligations are generally valued on the basis of valuations provided by third party pricing services, as derived from such services’ pricing models. Inputs to the models may include, but are not limited to, reported trades, executable bid and ask prices, broker/dealer quotations, prices or yields of securities with similar characteristics, interest rates, anticipated prepayments, benchmark curves or information pertaining to the issuer, as well as industry and economic events. The pricing services may use a matrix approach, which considers information regarding securities with similar characteristics to determine the valuation for a security. Short-term debt obligations purchased with a remaining maturity of sixty days or less for which a valuation from a third party pricing service is not readily available may be valued at amortized cost, which approximates fair value.

Affiliated Fund. The Fund and Portfolio may invest in Eaton Vance Cash Reserves Fund, LLC (Cash Reserves Fund), an affiliated investment company managed by Eaton Vance Management (EVM). While Cash Reserves Fund is not a registered money market mutual fund, it conducts all of its investment activities in accordance with the requirements of Rule 2a-7 under the 1940 Act. Investments in Cash Reserves Fund are valued at the closing net asset value per unit on the valuation day. Cash Reserves Fund generally values its investment securities based on available market quotations provided by a third party pricing service.

Fair Valuation. Investments for which valuations or market quotations are not readily available or are deemed unreliable are valued at fair value using methods determined in good faith by or at the direction of the Trustees of the Fund or Portfolio in a manner that most fairly reflects the security’s “fair value”, which is the amount that the Fund or Portfolio might reasonably expect to receive for the security upon its current sale in the ordinary course. Each such determination is based on a consideration of relevant factors, which are likely to vary from one pricing context to another. These factors may include, but are not limited to, the type of security, the existence of any contractual restrictions on the security’s disposition, the price and extent of public trading in similar securities of the issuer or of comparable companies or entities, quotations or relevant information obtained from broker/dealers or other market participants, information obtained from the issuer, analysts, and/or the appropriate stock exchange (for exchange-traded securities), an analysis of the company’s or entity’s financial statements, and an evaluation of the forces that influence the issuer and the market(s) in which the security is purchased and sold.

Additional valuation policies of the Fund are as follows:

Derivatives. Swaps are normally valued using valuations provided by a third party pricing service. Such pricing service valuations are based on the present value of fixed and projected floating rate cash flows over the term of the swap contract. Future cash flows on swaps are discounted to their present value using swap rates provided by electronic data services or by broker/dealers.

Additional valuation policies of the Portfolio are as follows:

Senior Floating-Rate Loans. Interests in senior floating-rate loans (Senior Loans) for which reliable market quotations are readily available are valued generally at the average mean of bid and ask quotations obtained from a third party pricing service. Other Senior Loans are valued at fair value by the investment adviser under procedures approved by the Trustees. In fair valuing a Senior Loan, the investment adviser utilizes one or more of the valuation techniques described in (i) through (iii) below to assess the likelihood that the borrower will make a full repayment of the loan underlying such Senior Loan


		16

Eaton Vance

Short Duration Inflation-Protected Income Fund

October 31, 2021

Notes to Financial Statements — continued

relative to yields on other Senior Loans issued by companies of comparable credit quality. If the investment adviser believes that there is a reasonable likelihood of full repayment, the investment adviser will determine fair value using a matrix pricing approach that considers the yield on the Senior Loan. If the investment adviser believes there is not a reasonable likelihood of full repayment, the investment adviser will determine fair value using analyses that include, but are not limited to: (i) a comparison of the value of the borrower’s outstanding equity and debt to that of comparable public companies; (ii) a discounted cash flow analysis; or (iii) when the investment adviser believes it is likely that a borrower will be liquidated or sold, an analysis of the terms of such liquidation or sale. In certain cases, the investment adviser will use a combination of analytical methods to determine fair value, such as when only a portion of a borrower’s assets are likely to be sold. In conducting its assessment and analyses for purposes of determining fair value of a Senior Loan, the investment adviser will use its discretion and judgment in considering and appraising relevant factors. Fair value determinations are made by the portfolio managers of the Portfolio based on information available to such managers. The portfolio managers of other funds managed by the investment adviser that invest in Senior Loans may not possess the same information about a Senior Loan borrower as the portfolio managers of the Portfolio. At times, the fair value of a Senior Loan determined by the portfolio managers of other funds managed by the investment adviser that invest in Senior Loans may vary from the fair value of the same Senior Loan determined by the portfolio managers of the Portfolio. The fair value of each Senior Loan is periodically reviewed and approved by the investment adviser’s Valuation Committee and by the Trustees based upon procedures approved by the Trustees. Junior Loans (i.e., subordinated loans and second lien loans) are valued in the same manner as Senior Loans.

Equity Securities. Equity securities listed on a U.S. securities exchange generally are valued at the last sale or closing price on the day of valuation or, if no sales took place on such date, at the mean between the closing bid and ask prices on the exchange where such securities are principally traded. Equity securities listed on the NASDAQ National Market System are valued at the NASDAQ official closing price. Unlisted or listed securities for which closing sales prices or closing quotations are not available are valued at the mean between the latest available bid and ask prices.

Derivatives. Forward foreign currency exchange contracts are generally valued at the mean of the average bid and average ask prices that are reported by currency dealers to a third party pricing service at the valuation time. Such third party pricing service valuations are supplied for specific settlement periods and the Portfolio’s forward foreign currency exchange contracts are valued at an interpolated rate between the closest preceding and subsequent settlement period reported by the third party pricing service.

Foreign Securities and Currencies. Foreign securities and currencies are valued in U.S. dollars, based on foreign currency exchange rate quotations supplied by a third party pricing service. The pricing service uses a proprietary model to determine the exchange rate. Inputs to the model include reported trades and implied bid/ask spreads.

B Income — The Fund’s net investment income or loss includes the Fund’s pro-rata share of the net investment income or loss of the Portfolio, less all actual and accrued expenses of the Fund. Interest income on direct investments is recorded on the basis of interest accrued, adjusted for amortization of premium or accretion of discount. Inflation adjustments to the principal amount of inflation-adjusted bonds and notes are reflected as interest income. Deflation adjustments to the principal amount of an inflation-adjusted bond or note are reflected as reductions to interest income to the extent of interest income previously recorded on such bond or note. Dividend income on direct investments is recorded on the ex-dividend date for dividends received in cash and/or securities.

C Federal Taxes — The Fund’s policy is to comply with the provisions of the Internal Revenue Code applicable to regulated investment companies and to distribute to shareholders each year substantially all of its net investment income, and all or substantially all of its net realized capital gains. Accordingly, no provision for federal income or excise tax is necessary.

As of October 31, 2021, the Fund had no uncertain tax positions that would require financial statement recognition, de-recognition, or disclosure. The Fund files a U.S. federal income tax return annually after its fiscal year-end, which is subject to examination by the Internal Revenue Service for a period of three years from the date of filing.

D Expenses — The majority of expenses of the Trust are directly identifiable to an individual fund. Expenses which are not readily identifiable to a specific fund are allocated taking into consideration, among other things, the nature and type of expense and the relative size of the funds.

E Use of Estimates — The preparation of the financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities at the date of the financial statements and the reported amounts of income and expense during the reporting period. Actual results could differ from those estimates.

F Indemnifications — Under the Trust’s organizational documents, its officers and Trustees may be indemnified against certain liabilities and expenses arising out of the performance of their duties to the Fund. Under Massachusetts law, if certain conditions prevail, shareholders of a Massachusetts business trust (such as the Trust) could be deemed to have personal liability for the obligations of the Trust. However, the Trust’s Declaration of Trust contains an express disclaimer of liability on the part of Fund shareholders and the By-laws provide that the Trust shall assume, upon request by the shareholder, the defense on behalf of any Fund shareholders. Moreover, the By-laws also provide for indemnification out of Fund property of any shareholder held personally liable solely by reason of being or having been a shareholder for all loss or expense arising from such liability. Additionally, in the normal course of business, the Fund enters into agreements with service providers that may contain indemnification clauses. The Fund’s maximum exposure under these arrangements is unknown as this would involve future claims that may be made against the Fund that have not yet occurred.

G Inflation Swaps — Swap contracts are privately negotiated agreements between the Fund and a counterparty. Certain swap contracts may be centrally cleared (“centrally cleared swaps”), whereby all payments made or received by the Fund pursuant to the contract are with a central clearing party (CCP)


		17

Eaton Vance

Short Duration Inflation-Protected Income Fund

October 31, 2021

Notes to Financial Statements — continued

rather than the original counterparty. The CCP guarantees the performance of the original parties to the contract. Upon entering into centrally cleared swaps, the Fund is required to deposit with the CCP, either in cash or securities, an amount of initial margin determined by the CCP, which is subject to adjustment.

Pursuant to inflation swap agreements, the Fund either makes floating-rate payments to the counterparty (or CCP in the case of centrally cleared swaps) based on a benchmark index in exchange for fixed-rate payments or the Fund makes fixed-rate payments to the counterparty (or CCP in the case of centrally cleared swaps) in exchange for floating-rate payments based on the return of a benchmark index. By design, the benchmark index is an inflation index, such as the Consumer Price Index. Payments received or made are recorded as realized gains or losses. During the term of the outstanding swap agreement, changes in the underlying value of the swap are recorded as unrealized gains or losses. For centrally cleared swaps, the daily change in valuation is recorded as a receivable or payable for variation margin and settled in cash with the CCP daily. The value of the swap is determined by changes in the relationship between the rate of interest and the benchmark index. The Fund is exposed to credit loss in the event of nonperformance by the swap counterparty. In the case of centrally cleared swaps, counterparty risk is minimal due to protections provided by the CCP. Risk may also arise from the unanticipated movements in value of interest rates or the index.

H Other — Investment transactions are accounted for on a trade date basis. Realized gains and losses on investments sold are determined on the basis of identified cost.

2 Distributions to Shareholders and Income Tax Information

It is the present policy of the Fund to declare and pay distributions quarterly of all or substantially all of its net investment income and to distribute annually all or substantially all of its net realized capital gains. Distributions of realized capital gains are made at least annually. Distributions are declared separately for each class of shares. Shareholders may reinvest income and capital gain distributions in additional shares of the same class of the Fund at the net asset value as of the reinvestment date or, at the election of the shareholder, receive distributions in cash. Distributions to shareholders are determined in accordance with income tax regulations, which may differ from U.S. GAAP. As required by U.S. GAAP, only distributions in excess of tax basis earnings and profits are reported in the financial statements as a return of capital. Permanent differences between book and tax accounting relating to distributions are reclassified to paid-in capital. For tax purposes, distributions from short-term capital gains are considered to be from ordinary income.

The tax character of distributions declared for the years ended October 31, 2021 and October 31, 2020 was as follows:


	Year Ended October 31,
	2021		2020

Ordinary income	$	10,564,748	$	4,570,866

As of October 31, 2021, the components of distributable earnings (accumulated loss) on a tax basis were as follows:



Undistributed ordinary income	$	614,714

Deferred capital losses		(10,432,620	)

Net unrealized appreciation		12,916,087

Distributable earnings	$	3,098,181

At October 31, 2021, the Fund, for federal income tax purposes, had deferred capital losses of $10,432,620 which would reduce its taxable income arising from future net realized gains on investment transactions, if any, to the extent permitted by the Internal Revenue Code, and thus would reduce the amount of distributions to shareholders, which would otherwise be necessary to relieve the Fund of any liability for federal income or excise tax. The deferred capital losses are treated as arising on the first day of the Fund’s next taxable year and retain the same short-term or long-term character as when originally deferred. Of the deferred capital losses at October 31, 2021, $1,705,835 are short-term and $8,726,785 are long-term.

The cost and unrealized appreciation (depreciation) of investments, including open derivative contracts, of the Fund at October 31, 2021, as determined on a federal income tax basis, were as follows:



Aggregate cost	$	406,035,907

Gross unrealized appreciation	$	13,067,425

Gross unrealized depreciation		(151,338	)

Net unrealized appreciation	$	12,916,087


		18

Eaton Vance

Short Duration Inflation-Protected Income Fund

October 31, 2021

Notes to Financial Statements — continued

3 Investment Adviser Fee and Other Transactions with Affiliates

The investment adviser fee is earned by EVM as compensation for investment advisory services rendered to the Fund. On March 1, 2021, Morgan Stanley acquired Eaton Vance Corp. (the “Transaction”) and EVM became an indirect, wholly-owned subsidiary of Morgan Stanley. In connection with the Transaction, the Fund entered into a new investment advisory agreement (the “New Agreement”) with EVM, which took effect on March 1, 2021. The Fund’s prior fee reduction agreement was incorporated into the New Agreement. Pursuant to the New Agreement (and the Fund’s investment advisory agreement and related fee reduction agreement with EVM in effect prior to March 1, 2021), the investment adviser fee is computed based on the Fund’s average daily net assets that are not invested in other investment companies for which EVM or its affiliates serve as investment adviser and receive an advisory fee at the following annual rates and is payable monthly:


Average Daily Net Assets	Annual Fee Rate

Up to $1 billion		0.45	%

$1 billion but less than $2.5 billion		0.43	%

$2.5 billion but less than $5 billion		0.41	%

$5 billion and over		0.40	%

To the extent the Fund’s assets are invested in the Portfolio, the Fund is allocated its share of the Portfolio’s investment adviser fee. The Portfolio has engaged Boston Management and Research (BMR) to render investment advisory services. For the year ended October 31, 2021, the Fund’s investment adviser fee totaled $1,226,914, of which $380,790 was allocated from the Portfolio and $846,124 was paid or accrued directly by the Fund. For the year ended October 31, 2021, the Fund’s investment adviser fee, including the investment adviser fee allocated from the Portfolio, was 0.45% of the Fund’s average daily net assets. EVM also serves as the administrator of the Fund, but currently receives no compensation. The Fund may invest its cash in Cash Reserves Fund. EVM does not currently receive a fee for advisory services provided to Cash Reserves Fund.

EVM has agreed to reimburse the Fund’s expenses to the extent that total annual operating expenses (relating to ordinary operating expenses only and excluding such expenses as borrowing costs, taxes or litigation expenses) exceed 0.75%, 1.50% and 0.50% of the Fund’s average daily net assets for Class A, Class C and Class I, respectively. This agreement may be changed or terminated after February 28, 2022. Pursuant to this agreement, EVM reimbursed expenses of $275,971 for the year ended October 31, 2021.

EVM provides sub-transfer agency and related services to the Fund pursuant to a Sub-Transfer Agency Support Services Agreement. For the year ended October 31, 2021, EVM earned $5,430 from the Fund pursuant to such agreement, which is included in transfer and dividend disbursing agent fees on the Statement of Operations. The Fund was informed that Eaton Vance Distributors, Inc. (EVD), an affiliate of EVM and the Fund’s principal underwriter, received $4,438 as its portion of the sales charge on sales of Class A shares for the year ended October 31, 2021. The Fund was informed that Morgan Stanley affiliated broker-dealers, which may be deemed to be affiliates of EVM, BMR and EVD, also received a portion of the sales charge on sales of Class A shares from March 1, 2021 through October 31, 2021 in the amount of $9,869. EVD also received distribution and service fees from Class A and Class C shares (see Note 4) and contingent deferred sales charges (see Note 5).

Trustees and officers of the Fund and the Portfolio who are members of EVM’s or BMR’s organizations receive remuneration for their services to the Fund out of the investment adviser fee. Certain officers and Trustees of the Fund and the Portfolio are officers of the above organizations.

4 Distribution Plans

The Fund has in effect a distribution plan for Class A shares (Class A Plan) pursuant to Rule 12b-1 under the 1940 Act. Pursuant to the Class A Plan, the Fund pays EVD a distribution and service fee of 0.25% per annum of its average daily net assets attributable to Class A shares for distribution services and facilities provided to the Fund by EVD, as well as for personal services and/or the maintenance of shareholder accounts. Distribution and service fees paid or accrued to EVD for the year ended October 31, 2021 amounted to $104,099 for Class A shares. The Fund also has in effect a distribution plan for Class C shares (Class C Plan) pursuant to Rule 12b-1 under the 1940 Act. Pursuant to the Class C Plan, the Fund pays EVD amounts equal to 0.75% per annum of its average daily net assets attributable to Class C shares for providing ongoing distribution services and facilities to the Fund. For the year ended October 31, 2021, the Fund paid or accrued to EVD $46,667 for Class C shares.

Pursuant to the Class C Plan, the Fund also makes payments of service fees to EVD, financial intermediaries and other persons in amounts equal to 0.25% per annum of its average daily net assets attributable to Class C shares. Service fees paid or accrued are for personal services and/or the maintenance of shareholder accounts. They are separate and distinct from the sales commissions and distribution fees payable to EVD. Service fees paid or accrued for the year ended October 31, 2021 amounted to $15,556 for Class C shares.

Distribution and service fees are subject to the limitations contained in the Financial Industry Regulatory Authority Rule 2341(d).


		19

Eaton Vance

Short Duration Inflation-Protected Income Fund

October 31, 2021

Notes to Financial Statements — continued

5 Contingent Deferred Sales Charges

A contingent deferred sales charge (CDSC) of 1% generally is imposed on redemptions of Class C shares made within 12 months of purchase. Class A shares may be subject to a 1% CDSC if redeemed within 18 months of purchase (depending on the circumstances of purchase). Generally, the CDSC is based upon the lower of the net asset value at date of redemption or date of purchase. No charge is levied on shares acquired by reinvestment of dividends or capital gain distributions. For the year ended October 31, 2021, the Fund was informed that EVD received approximately $1,000 and $100 of CDSCs paid by Class A and Class C shareholders, respectively.

6 Investment Transactions

For the year ended October 31, 2021, increases and decreases in the Fund’s investment in the Portfolio aggregated $78,852,868 and $11,800,234, respectively.

7 Purchases and Sales of Investments

Purchases and sales of investments by the Fund, other than short-term obligations, and including maturities and paydowns, for the year ended October 31, 2021 were as follows:


	Purchases		Sales

Investments (non-U.S. Government)	$	748,351	$	20,296,131

U.S. Government and Agency Securities		192,188,931		34,166,844

	$	192,937,282	$	54,462,975

8 Shares of Beneficial Interest

The Fund’s Declaration of Trust permits the Trustees to issue an unlimited number of full and fractional shares of beneficial interest (without par value). Such shares may be issued in a number of different series (such as the Fund) and classes. Transactions in Fund shares were as follows:


	Year Ended October 31,
Class A	2021			2020

Sales		3,900,661			1,188,329

Issued to shareholders electing to receive payments of distributions in Fund shares		145,514			62,874

Redemptions		(1,476,121	)		(1,369,080	)

Converted from Class C shares		114,710			22,168

Net increase (decrease)		2,684,764			(95,709	)

	Year Ended October 31,
Class C	2021			2020

Sales		758,124			52,089

Issued to shareholders electing to receive payments of distributions in Fund shares		19,750			9,324

Redemptions		(100,448	)		(248,403	)

Converted to Class A shares		(115,765	)		(22,344	)

Net increase (decrease)		561,661			(209,334	)


		20

Eaton Vance

Short Duration Inflation-Protected Income Fund

October 31, 2021

Notes to Financial Statements — continued


	Year Ended October 31,
Class I	2021			2020

Sales		26,310,010			7,819,261

Issued to shareholders electing to receive payments of distributions in Fund shares		851,543			399,047

Redemptions		(9,105,288	)		(13,872,490	)

Net increase (decrease)		18,056,265			(5,654,182	)

At October 31, 2021, donor advised and pooled income funds (established and maintained by a public charity) managed by EVM owned in the aggregate 13.50% of the value of the outstanding shares of the Fund.

9 Financial Instruments

The Fund may trade in financial instruments with off-balance sheet risk in the normal course of its investing activities. These financial instruments may include swap contracts and may involve, to a varying degree, elements of risk in excess of the amounts recognized for financial statement purposes. The notional or contractual amounts of these instruments represent the investment the Fund has in particular classes of financial instruments and do not necessarily represent the amounts potentially subject to risk. The measurement of the risks associated with these instruments is meaningful only when all related and offsetting transactions are considered. A summary of obligations under these financial instruments at October 31, 2021 is included in the Portfolio of Investments. At October 31, 2021, the Fund had sufficient cash and/or securities to cover commitments under these contracts.

The Fund is subject to interest rate risk in the normal course of pursuing its investment objective and its use of derivatives. The Fund enters into inflation swap agreements to swap nominal interest payments with respect to its investments in certain fixed or floating-rate debt (including floating-rate loans) for payments based on changes in the U.S. Consumer Price Index or other measures of inflation.

The Fund enters into swap contracts (other than centrally cleared swaps) that may contain provisions whereby the counterparty may terminate the contract under certain conditions, including but not limited to a decline in the Fund’s net assets below a certain level over a certain period of time, which would trigger a payment by the Fund for those derivatives in a liability position. At October 31, 2021, the Fund had no open derivatives with credit-related contingent features in a net liability position.

The over-the-counter (OTC) derivatives in which the Fund invests are subject to the risk that the counterparty to the contract fails to perform its obligations under the contract. To mitigate this risk, the Fund has entered into an International Swaps and Derivatives Association, Inc. Master Agreement (“ISDA Master Agreement”) or similar agreement with substantially all its derivative counterparties. An ISDA Master Agreement is a bilateral agreement between the Fund and a counterparty that governs certain OTC derivatives and typically contains, among other things, set-off provisions in the event of a default and/or termination event as defined under the relevant ISDA Master Agreement. Under an ISDA Master Agreement, the Fund may, under certain circumstances, offset with the counterparty certain derivative financial instruments’ payables and/or receivables with collateral held and/or posted and create one single net payment. The provisions of the ISDA Master Agreement typically permit a single net payment in the event of default including the bankruptcy or insolvency of the counterparty. However, bankruptcy or insolvency laws of a particular jurisdiction may impose restrictions on or prohibitions against the right of offset in bankruptcy or insolvency. Certain ISDA Master Agreements allow counterparties to OTC derivatives to terminate derivative contracts prior to maturity in the event the Fund’s net assets decline by a stated percentage or the Fund fails to meet the terms of its ISDA Master Agreements, which would cause the counterparty to accelerate payment by the Fund of any net liability owed to it.

The collateral requirements for derivatives traded under an ISDA Master Agreement are governed by a Credit Support Annex to the ISDA Master Agreement. Collateral requirements are determined at the close of business each day and are typically based on changes in market values for each transaction under an ISDA Master Agreement and netted into one amount for such agreement. Generally, the amount of collateral due from or to a counterparty is subject to a minimum transfer threshold amount before a transfer is required, which may vary by counterparty. Collateral pledged for the benefit of the Fund and/or counterparty is held in segregated accounts by the Fund’s custodian and cannot be sold, re-pledged, assigned or otherwise used while pledged. The portion of such collateral representing cash, if any, is reflected as deposits for derivatives collateral and, in the case of cash pledged by a counterparty for the benefit of the Fund, a corresponding liability on the Statement of Assets and Liabilities. Securities pledged by the Fund as collateral, if any, are identified as such in the Portfolio of Investments. The carrying amount of the liability for cash collateral due to brokers at October 31, 2021 approximated its fair value. If measured at fair value, such liability would have been considered as Level 2 in the fair value hierarchy (see Note 12) at October 31, 2021.


		21

Eaton Vance

Short Duration Inflation-Protected Income Fund

October 31, 2021

Notes to Financial Statements — continued

The fair value of open derivative instruments (not considered to be hedging instruments for accounting disclosure purposes) and whose primary underlying risk exposure is interest rate risk at October 31, 2021 was as follows:


	Fair Value
Derivative	Asset Derivative			Liability Derivative

Swap contracts	$	3,254,419	⁽¹⁾	$	—

Swap contracts (centrally cleared)		4,639,820	⁽²⁾		(81,540	)⁽²⁾

Total	$	7,894,239		$	(81,540	)

Derivatives not subject to master netting or similar agreements	$	4,639,820		$	(81,540	)

Total Derivatives subject to master netting or similar agreements	$	3,254,419		$	—

⁽¹⁾	Statement of Assets and Liabilities location: Receivable for open swap contracts; Distributable earnings.

⁽²⁾	Only the current day’s variation margin on centrally cleared swap contracts is reported within the Statement of Assets and Liabilities as Receivable or Payable for variation margin on centrally cleared swap contracts, as applicable.

The Fund’s derivative assets and liabilities at fair value by type, which are reported gross in the Statement of Assets and Liabilities, are presented in the table above. The following table presents the Fund’s derivative assets by counterparty, net of amounts available for offset under a master netting agreement and net of the related collateral received by the Fund for such assets as of October 31, 2021.


Counterparty	Derivative Assets Subject to Master Netting Agreement		Derivatives Available for Offset		Non-cash Collateral Received^(a)		Cash Collateral Received^(a)			Net Amount of Derivative Assets^(b)

Bank of America, N.A.	$	1,102,370	$	—	$	—	$	(1,102,370	)	$	—

Barclays Bank PLC		721,200		—		—		(540,000	)		181,200

Citibank, N.A.		543,804		—		—		(520,000	)		23,804

Goldman Sachs International		887,045		—		—		(810,000	)		77,045

	$	3,254,419	$	—	$	—	$	(2,972,370	)	$	282,049

^(a)	In some instances, the total collateral received and/or pledged may be more than the amount shown due to overcollateralization.

^(b)	Net amount represents the net amount due from the counterparty in the event of default.

The effect of derivative instruments (not considered to be hedging instruments for accounting disclosure purposes) on the Statement of Operations and whose primary underlying risk exposure is interest rate risk for the year ended October 31, 2021 was as follows:


Derivative	Realized Gain (Loss) on Derivatives Recognized in Income			Change in Unrealized Appreciation (Depreciation) on Derivatives Recognized in Income

Swap Contracts	$	(5,008	)⁽¹⁾	$	8,210,829	⁽²⁾

⁽¹⁾	Statement of Operations location: Net realized gain (loss) – Swap contracts.

⁽²⁾	Statement of Operations location: Change in unrealized appreciation (depreciation) – Swap contracts.

The average notional amount of swap contracts outstanding during the year ended October 31, 2021, which is indicative of the volume of this derivative type, was approximately $100,077,000.


		22

Eaton Vance

Short Duration Inflation-Protected Income Fund

October 31, 2021

Notes to Financial Statements — continued

10 Line of Credit

The Fund participates with other portfolios and funds managed by EVM and its affiliates in an $800 million unsecured line of credit agreement with a group of banks, which is in effect through October 25, 2022. Borrowings are made by the Fund solely for temporary purposes related to redemptions and other short-term cash needs. Interest is charged to the Fund based on its borrowings at an amount above either the Secured Overnight Financing Rate (SOFR) or Federal Funds rate. In addition, a fee computed at an annual rate of 0.15% on the daily unused portion of the line of credit is allocated among the participating portfolios and funds at the end of each quarter. In connection with the renewal of the agreement in October 2021, an arrangement fee totaling $150,000 was incurred that was allocated to the participating portfolios and funds. Because the line of credit is not available exclusively to the Fund, it may be unable to borrow some or all of its requested amounts at any particular time. The Fund did not have any significant borrowings or allocated fees during the year ended October 31, 2021.

11 Investments in Affiliated Funds

At October 31, 2021, the value of the Fund’s investment in affiliated funds was $9,713,035, which represents 2.3% of the Fund’s net assets. Transactions in affiliated funds by the Fund for the year ended October 31, 2021 were as follows:


Name	Value, beginning of period		Purchases		Sales proceeds			Net realized gain (loss)		Change in unrealized appreciation (depreciation)		Value, end of period		Dividend income		Units, end of period

Short-Term Investments

Eaton Vance Cash Reserves Fund, LLC	$	2,961,814	$	144,550,888	$	(137,799,719	)	$	52	$	—	$	9,713,035	$	3,156		9,713,035

12 Fair Value Measurements

Under generally accepted accounting principles for fair value measurements, a three-tier hierarchy to prioritize the assumptions, referred to as inputs, is used in valuation techniques to measure fair value. The three-tier hierarchy of inputs is summarized in the three broad levels listed below.

•

Level 1 – quoted prices in active markets for identical investments

•

Level 2 – other significant observable inputs (including quoted prices for similar investments, interest rates, prepayment speeds, credit risk, etc.)

•

Level 3 – significant unobservable inputs (including a fund’s own assumptions in determining the fair value of investments)

In cases where the inputs used to measure fair value fall in different levels of the fair value hierarchy, the level disclosed is determined based on the lowest level input that is significant to the fair value measurement in its entirety. The inputs or methodology used for valuing securities are not necessarily an indication of the risk associated with investing in those securities.


		23

Eaton Vance

Short Duration Inflation-Protected Income Fund

October 31, 2021

Notes to Financial Statements — continued

At October 31, 2021, the hierarchy of inputs used in valuing the Fund’s investments and open derivative instruments, which are carried at value, were as follows:


Asset Description	Level 1		Level 2			Level 3		Total

Investment in Affiliated Portfolio	$	118,849,044	$	—		$	—	$	118,849,044

Asset-Backed Securities		—		6,081,029			—		6,081,029

Commercial Mortgage-Backed Securities		—		1,796,524			—		1,796,524

U.S. Treasury Obligations		—		274,699,663			—		274,699,663

Short-Term Investments		—		9,713,035			—		9,713,035

Total Investments	$	118,849,044	$	292,290,251		$	—	$	411,139,295

Swap Contracts	$	—	$	7,894,239		$	—	$	7,894,239

Total	$	118,849,044	$	300,184,490		$	—	$	419,033,534

Liability Description

Swap Contracts	$	—	$	(81,540	)	$	—	$	(81,540	)

Total	$	—	$	(81,540	)	$	—	$	(81,540	)

13 Risks and Uncertainties

LIBOR Transition Risk

Certain instruments held by the Portfolio may pay an interest rate based on the London Interbank Offered Rate (“LIBOR”), which is the average offered rate for various maturities of short-term loans between certain major international banks. LIBOR is used throughout global banking and financial industries to determine interest rates for a variety of financial instruments (such as debt instruments and derivatives) and borrowing arrangements. The ICE Benchmark Administration Limited, the administrator of LIBOR, is expected to cease publishing certain LIBOR settings on December 31, 2021, and the remaining LIBOR settings on June 30, 2023. Although the transition process away from LIBOR has become increasingly well-defined in advance of the anticipated discontinuation, the impact on certain debt securities, derivatives and other financial instruments that utilize LIBOR remains uncertain. The phase-out of LIBOR may result in, among other things, increased volatility or illiquidity in markets for instruments based on LIBOR and changes in the value of such instruments.

Pandemic Risk

An outbreak of respiratory disease caused by a novel coronavirus was first detected in China in late 2019 and subsequently spread internationally. This coronavirus has resulted in closing borders, enhanced health screenings, changes to healthcare service preparation and delivery, quarantines, cancellations, disruptions to supply chains and customer activity, as well as general concern and uncertainty. Health crises caused by outbreaks, such as the coronavirus outbreak, may exacerbate other pre-existing political, social and economic risks and disrupt normal market conditions and operations. The impact of this outbreak has negatively affected the worldwide economy, the economies of individual countries, individual companies, and the market in general, and may continue to do so in significant and unforeseen ways, as may other epidemics and pandemics that may arise in the future. Any such impact could adversely affect the Fund’s performance, or the performance of the securities in which the Fund invests.


		24

Eaton Vance

Short Duration Inflation-Protected Income Fund

October 31, 2021

Report of Independent Registered Public Accounting Firm

To the Trustees of Eaton Vance Special Investment Trust and Shareholders of Eaton Vance Short Duration Inflation-Protected Income Fund:

Opinion on the Financial Statements and Financial Highlights

We have audited the accompanying statement of assets and liabilities of Eaton Vance Short Duration Inflation-Protected Income Fund (the “Fund”) (one of the funds constituting Eaton Vance Special Investment Trust), including the portfolio of investments, as of October 31, 2021, 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. In our opinion, the financial statements and financial highlights present fairly, in all material respects, the financial position of the Fund as of October 31, 2021, and 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 the financial highlights for each of the five years in the period then ended, in conformity with accounting principles generally accepted in the United States of America.

Basis for Opinion

These financial statements and financial highlights are the responsibility of the Fund’s management. Our responsibility is to express an opinion on the Fund’s financial statements and financial highlights 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 Fund 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 and financial highlights are free of material misstatement, whether due to error or fraud. The Fund is not required to have, nor were we engaged to perform, an audit of its 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 Fund’s internal control over financial reporting. Accordingly, we express no such opinion.

Our audits included performing procedures to assess the risks of material misstatement of the financial statements and financial highlights, 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 and financial highlights. 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 and financial highlights. Our procedures included confirmation of securities owned as of October 31, 2021, by correspondence with the custodian and brokers; when replies were not received from brokers, we performed other auditing procedures. We believe that our audits provide a reasonable basis for our opinion.

/s/ Deloitte & Touche LLP

Boston, Massachusetts

December 22, 2021

We have served as the auditor of one or more Eaton Vance investment companies since 1959.


		25

Eaton Vance

Short Duration Inflation-Protected Income Fund

October 31, 2021

Federal Tax Information (Unaudited)

The Form 1099-DIV you receive in February 2022 will show the tax status of all distributions paid to your account in calendar year 2021. Shareholders are advised to consult their own tax adviser with respect to the tax consequences of their investment in the Fund. As required by the Internal Revenue Code and/or regulations, shareholders must be notified regarding the status of 163(j) interest dividends.

163(j) Interest Dividends. For the fiscal year ended October 31, 2021, the Fund designates 96.53% of distributions from net investment income as a 163(j) interest dividend.


		26

Eaton Vance

Short Duration Inflation-Protected Income Fund

October 31, 2021

Liquidity Risk Management Program

The Fund has implemented a written liquidity risk management program (Program) and related procedures to manage its liquidity in accordance with Rule 22e-4 under the Investment Company Act of 1940, as amended (Liquidity Rule). The Liquidity Rule defines “liquidity risk” as the risk that a fund could not meet requests to redeem shares issued by the fund without significant dilution of the remaining investors’ interests in the fund. The Fund’s Board of Trustees/Directors has designated the investment adviser to serve as the administrator of the Program and the related procedures. The administrator has established a Liquidity Risk Management Oversight Committee (Committee) to perform the functions necessary to administer the Program. As part of the Program, the administrator is responsible for identifying illiquid investments and categorizing the relative liquidity of the Fund’s investments in accordance with the Liquidity Rule. Under the Program, the administrator assesses, manages, and periodically reviews the Fund’s liquidity risk, and is responsible for making certain reports to the Fund’s Board of Trustees/Directors and the Securities and Exchange Commission (SEC) regarding the liquidity of the Fund’s investments, and to notify the Board of Trustees/Directors and the SEC of certain liquidity events specified in the Liquidity Rule. The liquidity of the Fund’s portfolio investments is determined based on a number of factors including, but not limited to, relevant market, trading and investment-specific considerations under the Program.

At a meeting of the Fund’s Board of Trustees/Directors on June 8, 2021, the Committee provided a written report to the Fund’s Board of Trustees/Directors pertaining to the operation, adequacy, and effectiveness of implementation of the Program, as well as the operation of the highly liquid investment minimum (if applicable) for the period January 1, 2020 through December 31, 2020 (Review Period). The Program operated effectively during the Review Period, supporting the administrator’s ability to assess, manage and monitor Fund liquidity risk, including during periods of market volatility and net redemptions. During the Review Period, the Fund met redemption requests on a timely basis.

There can be no assurance that the Program will achieve its objectives in the future. Please refer to the Fund’s prospectus for more information regarding the Fund’s exposure to liquidity risk and other principal risks to which an investment in the Fund may be subject.


		27

Eaton Vance

Short Duration Inflation-Protected Income Fund

October 31, 2021

Management and Organization

Fund Management. The Trustees of Eaton Vance Special Investment Trust (the Trust), Eaton Vance Floating Rate Portfolio and Senior Debt Portfolio (collectively, the Portfolios) are responsible for the overall management and supervision of the Trust’s and Portfolios’ affairs. The Trustees and officers of the Trust and the Portfolios are listed below. Except as indicated, each individual has held the office shown or other offices in the same company for the last five years. Trustees and officers of the Trust and the Portfolios hold indefinite terms of office. The “Noninterested Trustees” consist of those Trustees who are not “interested persons” of the Trust and the Portfolios, as that term is defined under the 1940 Act. The business address of each Trustee and officer is Two International Place, Boston, Massachusetts 02110. As used below, “EVC” refers to Eaton Vance Corp., “EV” refers to EV LLC, “EVM” refers to Eaton Vance Management, “BMR” refers to Boston Management and Research and “EVD” refers to Eaton Vance Distributors, Inc. EV is the trustee of each of EVM and BMR. Effective March 1, 2021, each of EVM, BMR, EVD and EV are indirect, wholly owned subsidiaries of Morgan Stanley. Each officer affiliated with EVM may hold a position with other EVM affiliates that is comparable to his or her position with EVM listed below. Each Trustee oversees 138 portfolios (with the exception of Messrs. Faust and Wennerholm and Ms. Frost who oversee 137 portfolios) in the Eaton Vance Complex (including all master and feeder funds in a master feeder structure). Each officer serves as an officer of certain other Eaton Vance funds. Each Trustee and officer serves until his or her successor is elected.


Name and Year of Birth	Trust/Portfolio Position(s)	Trustee Since⁽¹⁾	Principal Occupation(s) and Other Directorships During Past Five Years and Other Relevant Experience

Interested Trustee

Thomas E. Faust Jr. 1958	Trustee	2007	Chairman of Morgan Stanley Investment Management, Inc. (MSIM), member of the Board of Managers and President of EV, Chief Executive Officer of EVM and BMR, and Director of EVD. Formerly, Chairman, Chief Executive Officer and President of EVC. Trustee and/or officer of 137 registered investment companies. Mr. Faust is an interested person because of his positions with MSIM, BMR, EVM, EVD, and EV, which are affiliates of the Trust and Portfolio, and his former position with EVC, which was an affiliate of the Trust and Portfolio prior to March 1, 2021. Other Directorships in the Last Five Years. Formerly, Director of EVC (2007-2021) and Hexavest Inc. (investment management firm) (2012-2021).

Noninterested Trustees

Mark R. Fetting 1954	Trustee	2016	Private investor. Formerly held various positions at Legg Mason, Inc. (investment management firm) (2000-2012), including President, Chief Executive Officer, Director and Chairman (2008-2012), Senior Executive Vice President (2004-2008) and Executive Vice President (2001-2004). Formerly, President of Legg Mason family of funds (2001-2008). Formerly, Division President and Senior Officer of Prudential Financial Group, Inc. and related companies (investment management firm) (1991-2000). Other Directorships in the Last Five Years. None.

Cynthia E. Frost 1961	Trustee	2014	Private investor. Formerly, Chief Investment Officer of Brown University (university endowment) (2000-2012). Formerly, Portfolio Strategist for Duke Management Company (university endowment manager) (1995-2000). Formerly, Managing Director, Cambridge Associates (investment consulting company) (1989-1995). Formerly, Consultant, Bain and Company (management consulting firm) (1987-1989). Formerly, Senior Equity Analyst, BA Investment Management Company (1983-1985). Other Directorships in the Last Five Years. None.

George J. Gorman 1952	Chairperson of the Board and Trustee	2021 (Chairperson) and 2014 (Trustee)	Principal at George J. Gorman LLC (consulting firm). Formerly, Senior Partner at Ernst & Young LLP (a registered public accounting firm) (1974-2009). Other Directorships in the Last Five Years. None.

Valerie A. Mosley 1960	Trustee	2014	Chairwoman and Chief Executive Officer of Valmo Ventures (a consulting and investment firm). Founder of Upward Wealth, Inc., dba BrightUP, a fintech platform. Formerly, Partner and Senior Vice President, Portfolio Manager and Investment Strategist at Wellington Management Company, LLP (investment management firm) (1992-2012). Formerly, Chief Investment Officer, PG Corbin Asset Management (1990-1992). Formerly worked in institutional corporate bond sales at Kidder Peabody (1986-1990). Other Directorships in the Last Five Years. Director of DraftKings, Inc. (digital sports entertainment and gaming company) (since September 2020). Director of Groupon, Inc. (e-commerce provider) (since April 2020). Director of Envestnet, Inc. (provider of intelligent systems for wealth management and financial wellness) (since 2018). Formerly, Director of Dynex Capital, Inc. (mortgage REIT) (2013-2020).


		28

Eaton Vance

Short Duration Inflation-Protected Income Fund

October 31, 2021

Management and Organization — continued


Name and Year of Birth	Trust/Portfolio Position(s)	Trustee Since⁽¹⁾	Principal Occupation(s) and Other Directorships During Past Five Years and Other Relevant Experience

Noninterested Trustees (continued)

William H. Park 1947	Trustee	2003	Private investor. Formerly, Consultant (management and transactional) (2012-2014). Formerly, Chief Financial Officer, Aveon Group L.P. (investment management firm) (2010-2011). Formerly, Vice Chairman, Commercial Industrial Finance Corp. (specialty finance company) (2006-2010). Formerly, President and Chief Executive Officer, Prizm Capital Management, LLC (investment management firm) (2002-2005). Formerly, Executive Vice President and Chief Financial Officer, United Asset Management Corporation (investment management firm) (1982-2001). Formerly, Senior Manager, Price Waterhouse (now PricewaterhouseCoopers) (a registered public accounting firm) (1972-1981). Other Directorships in the Last Five Years. None.

Helen Frame Peters 1948	Trustee	2008	Professor of Finance, Carroll School of Management, Boston College. Formerly, Dean, Carroll School of Management, Boston College (2000-2002). Formerly, Chief Investment Officer, Fixed Income, Scudder Kemper Investments (investment management firm) (1998-1999). Formerly, Chief Investment Officer, Equity and Fixed Income, Colonial Management Associates (investment management firm) (1991-1998). Other Directorships in the Last Five Years. None.

Keith Quinton 1958	Trustee	2018	Private investor, researcher and lecturer. Formerly, Independent Investment Committee Member at New Hampshire Retirement System (2017-2021). Formerly, Portfolio Manager and Senior Quantitative Analyst at Fidelity Investments (investment management firm) (2001-2014). Other Directorships in the Last Five Years. Formerly, Director (2016-2021) and Chairman (2019-2021) of New Hampshire Municipal Bond Bank.

Marcus L. Smith 1966	Trustee	2018	Private investor. Formerly, Portfolio Manager at MFS Investment Management (investment management firm) (1994-2017). Other Directorships in the Last Five Years. Director of First Industrial Realty Trust, Inc. (an industrial REIT) (since 2021). Director of MSCI Inc. (global provider of investment decision support tools) (since 2017). Formerly, Director of DCT Industrial Trust Inc. (logistics real estate company) (2017-2018).

Susan J. Sutherland 1957	Trustee	2015	Private investor. Director of Ascot Group Limited and certain of its subsidiaries (insurance and reinsurance) (since 2017). Formerly, Director of Hagerty Holding Corp. (insurance) (2015-2018) and Montpelier Re Holdings Ltd. (insurance and reinsurance) (2013-2015). Formerly, Associate, Counsel and Partner at Skadden, Arps, Slate, Meagher & Flom LLP (law firm) (1982-2013). Other Directorships in the Last Five Years. Director of Kairos Acquisition Corp. (insurance/InsurTech acquisition company) (since 2021).

Scott E. Wennerholm 1959	Trustee	2016	Private investor. Formerly, Trustee at Wheelock College (postsecondary institution) (2012-2018). Formerly, Consultant at GF Parish Group (executive recruiting firm) (2016-2017). Formerly, Chief Operating Officer and Executive Vice President at BNY Mellon Asset Management (investment management firm) (2005-2011). Formerly, Chief Operating Officer and Chief Financial Officer at Natixis Global Asset Management (investment management firm) (1997-2004). Formerly, Vice President at Fidelity Investments Institutional Services (investment management firm) (1994-1997). Other Directorships in the Last Five Years. None.


Name and Year of Birth	Trust/Portfolio Position(s)	Officer Since⁽²⁾	Principal Occupation(s) During Past Five Years

Principal Officers who are not Trustees

Eric A. Stein 1980	President	2020	Vice President and Chief Investment Officer, Fixed Income of EVM and BMR. Prior to November 1, 2020, Mr. Stein was a co-Director of Eaton Vance’s Global Income Investments. Also Vice President of Calvert Research and Management (“CRM”).

Deidre E. Walsh 1971	Vice President and Chief Legal Officer	2009	Vice President of EVM and BMR. Also Vice President of CRM.

James F. Kirchner 1967	Treasurer	2007	Vice President of EVM and BMR. Also Vice President of CRM.


		29

Eaton Vance

Short Duration Inflation-Protected Income Fund

October 31, 2021

Management and Organization — continued


Name and Year of Birth	Trust/Portfolio Position(s)	Officer Since⁽²⁾	Principal Occupation(s) During Past Five Years

Principal Officers who are not Trustees (continued)

Kimberly M. Roessiger 1985	Secretary	2021	Vice President of EVM and BMR.

Richard F. Froio 1968	Chief Compliance Officer	2017	Vice President of EVM and BMR since 2017. Formerly, Deputy Chief Compliance Officer (Adviser/Funds) and Chief Compliance Officer (Distribution) at PIMCO (2012-2017) and Managing Director at BlackRock/Barclays Global Investors (2009-2012).

⁽¹⁾	Year first appointed to serve as Trustee for a fund in the Eaton Vance family of funds. Each Trustee has served continuously since appointment unless indicated otherwise.

⁽²⁾	Year first elected to serve as officer of a fund in the Eaton Vance family of funds when the officer has served continuously. Otherwise, year of most recent election as an officer of a fund in the Eaton Vance family of funds. Titles may have changed since initial election.

The SAI for the Fund includes additional information about the Trustees and officers of the Fund and the Portfolios and can be obtained without charge on Eaton Vance’s website at www.eatonvance.com or by calling 1-800-262-1122.


		30

Eaton Vance Funds


Privacy Notice		April 2021



FACTS		WHAT DOES EATON VANCE DO WITH YOUR PERSONAL INFORMATION?



Why?		Financial companies choose how they share your personal information. Federal law gives consumers the right to limit some but not all sharing. Federal law also requires us to tell you how we collect, share, and protect your personal information. Please read this notice carefully to understand what we do.


What?		The types of personal information we collect and share depend on the product or service you have with us. This information can include: ^∎ Social Security number and income ^∎ investment experience and risk tolerance ^∎ checking account number and wire transfer instructions


How?		All financial companies need to share customers’ personal information to run their everyday business. In the section below, we list the reasons financial companies can share their customers’ personal information; the reasons Eaton Vance chooses to share; and whether you can limit this sharing.


Reasons we can share your personal information	Does Eaton Vance share?	Can you limit this sharing?
For our everyday business purposes — such as to process your transactions, maintain your account(s), respond to court orders and legal investigations, or report to credit bureaus	Yes	No
For our marketing purposes — to offer our products and services to you	Yes	No
For joint marketing with other financial companies	No	We don’t share
For our investment management affiliates’ everyday business purposes — information about your transactions, experiences, and creditworthiness	Yes	Yes
For our affiliates’ everyday business purposes — information about your transactions and experiences	Yes	No
For our affiliates’ everyday business purposes — information about your creditworthiness	No	We don’t share
For our investment management affiliates to market to you	Yes	Yes
For our affiliates to market to you	No	We don’t share
For nonaffiliates to market to you	No	We don’t share


To limit our sharing		Call toll-free 1-800-262-1122 or email: EVPrivacy@eatonvance.com Please note: If you are a new customer, we can begin sharing your information 30 days from the date we sent this notice. When you are no longer our customer, we continue to share your information as described in this notice. However, you can contact us at any time to limit our sharing.



Questions?		Call toll-free 1-800-262-1122 or email: EVPrivacy@eatonvance.com


		31

Eaton Vance Funds


Privacy Notice — continued		April 2021


Page 2


Who we are
Who is providing this notice?		Eaton Vance Management, Eaton Vance Distributors, Inc., Eaton Vance Trust Company, Eaton Vance Management (International) Limited, Eaton Vance Advisers International Ltd., Eaton Vance Global Advisors Limited, Eaton Vance Management’s Real Estate Investment Group, Boston Management and Research, Calvert Research and Management, Eaton Vance and Calvert Fund Families and our investment advisory affiliates (“Eaton Vance”) (see Investment Management Affiliates definition below)
What we do
How does Eaton Vance protect my personal information?		To protect your personal information from unauthorized access and use, we use security measures that comply with federal law. These measures include computer safeguards and secured files and buildings. We have policies governing the proper handling of customer information by personnel and requiring third parties that provide support to adhere to appropriate security standards with respect to such information.
How does Eaton Vance collect my personal information?		We collect your personal information, for example, when you ^∎ open an account or make deposits or withdrawals from your account ^∎ buy securities from us or make a wire transfer ^∎ give us your contact information We also collect your personal information from others, such as credit bureaus, affiliates, or other companies.
Why can’t I limit all sharing?		Federal law gives you the right to limit only ^∎ sharing for affiliates’ everyday business purposes — information about your creditworthiness ^∎ affiliates from using your information to market to you ^∎ sharing for nonaffiliates to market to you State laws and individual companies may give you additional rights to limit sharing. See below for more on your rights under state law.
Definitions
Investment Management Affiliates		Eaton Vance Investment Management Affiliates include registered investment advisers, registered broker-dealers, and registered and unregistered funds. Investment Management Affiliates does not include entities associated with Morgan Stanley Wealth Management, such as Morgan Stanley Smith Barney LLC and Morgan Stanley & Co.
Affiliates		Companies related by common ownership or control. They can be financial and nonfinancial companies. ^∎ Our affiliates include companies with a Morgan Stanley name and financial companies such as Morgan Stanley Smith Barney LLC and Morgan Stanley & Co.
Nonaffiliates		Companies not related by common ownership or control. They can be financial and nonfinancial companies. ^∎ Eaton Vance does not share with nonaffiliates so they can market to you.
Joint marketing		A formal agreement between nonaffiliated financial companies that together market financial products or services to you. ^∎ Eaton Vance doesn’t jointly market.
Other important information
Vermont: Except as permitted by law, we will not share personal information we collect about Vermont residents with Nonaffiliates unless you provide us with your written consent to share such information. California: Except as permitted by law, we will not share personal information we collect about California residents with Nonaffiliates and we will limit sharing such personal information with our Affiliates to comply with California privacy laws that apply to us.


		32

Eaton Vance Funds

IMPORTANT NOTICES

Delivery of Shareholder Documents. The Securities and Exchange Commission (SEC) permits funds to deliver only one copy of shareholder documents, including prospectuses, proxy statements and shareholder reports, to fund investors with multiple accounts at the same residential or post office box address. This practice is often called “householding” and it helps eliminate duplicate mailings to shareholders. Eaton Vance, or your financial intermediary, may household the mailing of your documents indefinitely unless you instruct Eaton Vance, or your financial intermediary, otherwise. If you would prefer that your Eaton Vance documents not be householded, please contact Eaton Vance at 1-800-262-1122, or contact your financial intermediary. Your instructions that householding not apply to delivery of your Eaton Vance documents will typically be effective within 30 days of receipt by Eaton Vance or your financial intermediary.

Portfolio Holdings. Each Eaton Vance Fund and its underlying Portfolio(s) (if applicable) files a schedule of portfolio holdings on Part F to Form N-PORT with the SEC. Certain information filed on Form N-PORT may be viewed on the Eaton Vance website at www.eatonvance.com, by calling Eaton Vance at 1-800-262-1122 or in the EDGAR database on the SEC’s website at www.sec.gov.

Proxy Voting. From time to time, funds are required to vote proxies related to the securities held by the funds. The Eaton Vance Funds or their underlying Portfolios (if applicable) vote proxies according to a set of policies and procedures approved by the Funds’ and Portfolios’ Boards. You may obtain a description of these policies and procedures and information on how the Funds or Portfolios voted proxies relating to portfolio securities during the most recent 12-month period ended June 30, without charge, upon request, by calling 1-800-262-1122 and by accessing the SEC’s website at www.sec.gov.


		33

This Page Intentionally Left Blank

Investment Adviser and Administrator of Eaton Vance Short Duration Inflation-Protected Income Fund

Eaton Vance Management

Two International Place

Boston, MA 02110

Principal Underwriter*

Eaton Vance Distributors, Inc.

Two International Place

Boston, MA 02110

(617) 482-8260

Custodian

State Street Bank and Trust Company

State Street Financial Center, One Lincoln Street

Boston, MA 02111

Transfer Agent

BNY Mellon Investment Servicing (US) Inc.

Attn: Eaton Vance Funds

P.O. Box 9653

Providence, RI 02940-9653

(800) 262-1122

Independent Registered Public Accounting Firm

Deloitte & Touche LLP

200 Berkeley Street

Boston, MA 02116-5022

Fund Offices

Two International Place

Boston, MA 02110

FINRA BrokerCheck. Investors may check the background of their Investment Professional by contacting the Financial Industry Regulatory Authority (FINRA). FINRA BrokerCheck is a free tool to help investors check the professional background of current and former FINRA-registered securities firms and brokers. FINRA BrokerCheck is available by calling 1-800-289-9999 and at www.FINRA.org. The FINRA BrokerCheck brochure describing this program is available to investors at www.FINRA.org.

LOGO

4596 10.31.21

Item 2.

Code of Ethics

The registrant (sometimes referred to as the “Fund”) has adopted a code of ethics applicable to its Principal Executive Officer, Principal Financial Officer and Principal Accounting Officer. The registrant undertakes to provide a copy of such code of ethics to any person upon request, without charge, by calling 1-800-262-1122. The registrant has not amended the code of ethics as described in Form N-CSR during the period covered by this report. The registrant has not granted any waiver, including an implicit waiver, from a provision of the code of ethics as described in Form N-CSR during the period covered by this report.

Item 3.

Audit Committee Financial Expert

The registrant’s Board of Trustees (the “Board”) has designated George J. Gorman, William H. Park and Scott E. Wennerholm, each an independent trustee, as audit committee financial experts. Mr. Gorman is a certified public accountant who is the Principal at George J. Gorman LLC (a consulting firm). Previously, Mr. Gorman served in various capacities at Ernst & Young LLP (a registered public accounting firm), including as Senior Partner. Mr. Gorman also has experience serving as an independent trustee and audit committee financial

expert of other mutual fund complexes. Mr. Park is a certified public accountant who is a private investor. Previously, he served as a consultant, as the Chief Financial Officer of Aveon Group, L.P. (an investment management firm), as the Vice Chairman of Commercial Industrial Finance Corp. (specialty finance company), as President and Chief Executive Officer of Prizm Capital Management, LLC (investment management firm), as Executive Vice President and Chief Financial Officer of United Asset Management Corporation (an institutional investment management firm) and as a Senior Manager at Price Waterhouse (now PricewaterhouseCoopers) (a registered public accounting firm). Mr. Wennerholm is a private investor. Previously, Mr. Wennerholm served as a Trustee at Wheelock College (postsecondary institution), as a Consultant at GF Parish Group (executive recruiting firm), Chief Operating Officer and Executive Vice President at BNY Mellon Asset Management (investment management firm), Chief Operating Officer and Chief Financial Officer at Natixis Global Asset Management (investment management firm), and Vice President at Fidelity Investments Institutional Services (investment management firm).

Item 4.

Principal Accountant Fees and Services

Eaton Vance Short Duration Inflation-Protected Income Fund (the “Fund(s)”) a series of Eaton Vance Special Investment Trust (the “Trust”), a Massachusetts business trust, which, including the Funds, contains a total of 9 series (the “Series”). The Trust is registered under the Investment Company Act of 1940 as an open-end management investment company. This Form N-CSR relates to the Fund’s annual report.

(a)-(d)

The following table presents the aggregate fees billed to the fund for the funds’ fiscal years ended October 31, 2020 and October 31, 2021 by the Fund’s principal accountant, Deloitte & Touche LLP (“D&T”), for professional services rendered for the audit of the fund’s annual financial statements and fees billed for other services rendered by D&T during such periods.


Eaton Vance Short Duration Inflation-Protected Income Fund Fiscal Years Ended	10/31/20		10/31/21
Audit Fees	$	39,350	$	40,350
Audit-Related Fees⁽¹⁾	$	0	$	0
Tax Fees⁽²⁾	$	8,572	$	8,922
All Other Fees⁽³⁾	$	0	$	0

Total	$	47,922	$	49,272

⁽¹⁾	Audit-related fees consist of the aggregate fees billed for assurance and related services that are reasonably related to the performance of the audit of financial statements and are not reported under the category of audit fees.

⁽²⁾	Tax fees consist of the aggregate fees billed for professional services rendered by the principal accountant relating to tax compliance, tax advice, and tax planning and specifically include fees for tax return preparation.

⁽³⁾	All other fees consist of the aggregate fees billed for products and services provided by the principal accountant other than audit, audit-related, and tax services.

The various Series comprising the Trust have differing fiscal year ends (October 31 or December 31). The following table presents the aggregate audit, audit-related, tax, and other fees billed to all of the Series in the Trust by D&T for the last two fiscal years of each Series.


Fiscal Years Ended*	12/31/19		10/31/20		12/31/20		10/31/21
Audit Fees	$	283,450	$	39,350	$	283,450	$	40,350
Audit-Related Fees⁽¹⁾	$	0	$	0	$	0	$	0
Tax Fees⁽²⁾	$	119,852	$	8,572	$	113,037	$	8,922
All Other Fees⁽³⁾	$	0	$	0	$	0	$	0

Total	$	403,302	$	47,922	$	396,487	$	49,272

⁽¹⁾	Audit-related fees consist of the aggregate fees billed for assurance and related services that are reasonably related to the performance of the audit of the registrant’s financial statements and are not reported under the category of audit fees.

⁽²⁾	Tax fees consist of the aggregate fees billed for professional services rendered by the principal accountant relating to tax compliance, tax advice, and tax planning and specifically include fees for tax return preparation and other tax related compliance/planning matters.

⁽³⁾	All other fees consist of the aggregate fees billed for products and services provided by the principal accountant other than audit, audit-related, and tax services.

(e)(1) The registrant’s audit committee has adopted policies and procedures relating to the pre-approval of services provided by the registrant’s principal accountant (the “Pre-Approval Policies”). The Pre-Approval Policies establish a framework intended to assist the audit committee in the proper discharge of its pre-approval responsibilities. As a general matter, the Pre-Approval Policies (i) specify certain types of audit, audit-related, tax, and other services determined to be pre-approved by the audit committee; and (ii) delineate specific procedures governing the mechanics of the pre-approval process, including the approval and monitoring of audit and non-audit service fees. Unless a service is specifically pre-approved under the Pre-Approval Policies, it must be separately pre-approved by the audit committee.

The Pre-Approval Policies and the types of audit and non-audit services pre-approved therein must be reviewed and ratified by the registrant’s audit committee at least annually. The registrant’s audit committee maintains full responsibility for the appointment, compensation, and oversight of the work of the registrant’s principal accountant.

(e)(2) No services described in paragraphs (b)-(d) above were approved by the registrant’s audit committee pursuant to the “de minimis exception” set forth in Rule 2-01(c)(7)(i)(C) of Regulation S-X.

(f) Not applicable.

(g) The following table presents (i) the aggregate non-audit fees (i.e., fees for audit-related, tax, and other services) billed for services rendered to all of the Series in the Trust by D&T for the last two fiscal years of each Series; and (ii) the aggregate non-audit fees (i.e., fees for audit-related, tax, and other services) billed to the Eaton Vance organization by D&T for the last two fiscal years of each Series.


Fiscal Years Ended*	12/31/19		10/31/20		12/31/20		10/31/21
Registrant⁽¹⁾	$	119,852	$	8,572	$	113,037	$	8,922
Eaton Vance⁽²⁾	$	59,903	$	51,800	$	150,300	$	51,800

⁽¹⁾	Includes all of the Series of the Trust. During the fiscal years reported above, certain of the Funds were “feeder” funds in a “master-feeder” fund structure or funds of funds.

⁽²⁾	Various subsidiaries of Morgan Stanley act in either an investment advisory and/or service provider capacity with respect to the Series and/or their respective “master” funds (if applicable).

(h) The registrant’s audit committee has considered whether the provision by the registrant’s principal accountant of non-audit services to the registrant’s investment adviser and any entity controlling, controlled by, or under common control with the adviser that provides ongoing services to the registrant that were not pre-approved pursuant to Rule 2-01(c)(7)(ii) of Regulation S-X is compatible with maintaining the principal accountant’s independence.

Item 5.

Audit Committee of Listed Registrants

Not applicable.

Item 6.

Schedule of Investments

Please see schedule of investments contained in the Report to Stockholders included under Item 1 of this Form N-CSR.

Item 7.

Disclosure of Proxy Voting Policies and Procedures for Closed-End Management Investment Companies

Not applicable.

Item 8.

Portfolio Managers of Closed-End Management Investment Companies

Not applicable.

Item 9.

Purchases of Equity Securities by Closed-End Management Investment Company and Affiliated Purchasers

Not applicable.

Item 10.

Submission of Matters to a Vote of Security Holders

No material changes.

Item 11.

Controls and Procedures

(a) It is the conclusion of the registrant’s principal executive officer and principal financial officer that the effectiveness of the registrant’s current disclosure controls and procedures (such disclosure controls and procedures having been evaluated within 90 days of the date of this filing) provide reasonable assurance that the information required to be disclosed by the registrant has been recorded, processed, summarized and reported within the time period specified in the Commission’s rules and forms and that the information required to be disclosed by the registrant has been accumulated and communicated to the registrant’s principal executive officer and principal financial officer in order to allow timely decisions regarding required disclosure.

(b) There have been no changes in the registrant’s internal controls over financial reporting 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.

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

Not applicable.

Item 13. Exhibits


(a)(1)		Registrant’s Code of Ethics – Not applicable (please see Item 2).

(a)(2)(i)		Treasurer’s Section 302 certification.

(a)(2)(ii)		President’s Section 302 certification.

(b)		Combined Section 906 certification.

Signatures

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.


Eaton Vance Special Investment Trust

By:		/s/ Eric A. Stein
		Eric A. Stein
		President

Date:		December 23, 2021

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:		/s/ James F. Kirchner
		James F. Kirchner
		Treasurer

Date:		December 23, 2021

By:		/s/ Eric A. Stein
		Eric A. Stein
		President

Date:		December 23, 2021

Eaton Vance Special Investment Trust N-CSRCertified annual shareholder report (management investment company)