PIMCO Dynamic Income Fund (PDI) N-CSRCertified annual shareholder report (management investment company)

dates with respect to interest accrual time periods also for the principal purpose of generating distributable gains (characterized as ordinary income for tax purposes) that are not part of a Fund’s duration or yield curve management strategies. In such a “paired swap transaction”, a Fund would generally enter into one or more interest rate swap agreements whereby a Fund agrees to make regular payments starting at the time the Fund enters into the agreements equal to a floating interest rate in return for payments equal to a fixed interest rate (the “initial leg”). A Fund would also enter into one or more interest rate swap agreements on the same underlying instrument, but take the opposite position (i.e., in this example, a Fund would make regular payments equal to a fixed interest rate in return for receiving payments equal to a floating interest rate) with respect to a contract whereby the payment obligations do not commence until a date following the commencement of the initial leg (the “forward leg”).

A Fund may engage in investment strategies, including those that employ the use of paired swaps transactions, the use of interest rate swaps to seek to capitalize on differences between short-term and long-term interest rates and other derivatives transactions, to, among other things, seek to generate current, distributable income, even if such strategies could potentially result in declines in the Fund’s net asset value (“NAV”). A Fund’s income and gain-generating strategies, including certain derivatives strategies, may generate current income and gains taxable as ordinary income sufficient to support monthly distributions even in situations when a Fund has experienced a decline in net assets due to, for example, adverse changes in the broad U.S. or non-U.S. equity markets or a Fund’s debt investments, or arising from its use of derivatives. For instance, a portion of a Fund’s monthly distributions may be sourced from paired swap transactions utilized to produce current distributable ordinary income for tax purposes on the initial leg, with a substantial possibility that a Fund will later realize a corresponding capital loss and potential decline in its NAV with respect to the forward leg (to the extent there are not corresponding offsetting capital gains being generated from other sources). Because some or all of these transactions may generate capital losses without corresponding offsetting capital gains, portions of a Fund’s distributions recognized as ordinary income for tax purposes (such as from paired swap transactions) may be economically similar to a taxable return of capital when considered together with such capital losses.

Classifications of the Funds’ portfolio holdings in this report are made according to financial reporting standards. The classification of a particular portfolio holding as shown in the Allocation Breakdown and Schedule of Investments or Consolidated Schedule of Investments, as applicable, and other sections of this report may differ from the classification used for the Funds’ compliance calculations, including

fallbacks, statutory requirements or otherwise may also result in a reduction in the value of certain instruments held by a Fund or a reduction in the effectiveness of related Fund transactions such as hedges. In addition, an instrument’s transition to a replacement rate could result in variations in the reported yields of a Fund that holds such instrument. Any such effects of the transition away from LIBOR, as well as other unforeseen effects, could result in losses to a Fund.

The common shares of the Funds trade on the New York Stock Exchange. As with any stock, the price of a Fund’s common shares will fluctuate with market conditions and other factors. If you sell your common shares of a Fund, the price received may be more or less than your original investment. Shares of closed-end management investment companies, such as the Funds, frequently trade at a discount from their NAV and may trade at a price that is less than the initial offering price and/or the NAV of such shares. Further, if a Fund’s shares trade at a price that is more than the initial offering price and/or the NAV of such shares, including at a substantial premium and/or for an extended period of time, there is no assurance that any such premium will be sustained for any period of time and will not decrease, or that the shares will not trade at a discount to NAV thereafter.

U.S. and global markets have experienced increased volatility, including as a result of the failures of certain U.S. and non-U.S. banks in 2023, which could be harmful to the Funds and issuers in which they invest. For example, if a bank at which a Fund or issuer has an account fails, any cash or other assets in bank or custody accounts, which may be substantial in size, could be temporarily inaccessible or permanently lost by the Fund or issuer. If a bank that provides a subscription line credit facility, asset-based facility, other credit facility and/or other services to an issuer or to a fund fails, the issuer or fund could be unable to draw funds under its credit facilities or obtain replacement credit facilities or other services from other lending institutions with similar terms.

Issuers in which a Fund may invest can be affected by volatility in the banking sector. Even if banks used by issuers in which the Funds invest remain solvent, volatility in the banking sector could contribute to, cause or intensify an economic recession, increase the costs of capital and banking services or result in the issuers being unable to obtain or refinance indebtedness at all or on as favorable terms as could otherwise have been obtained. Potential impacts to funds and issuers resulting from changes in the banking sector, market conditions and potential legislative or regulatory responses are uncertain. Such conditions and responses, as well as a changing interest rate environment, can contribute to decreased market liquidity and erode the value of certain holdings, including those of U.S. and non-U.S. banks. Continued market volatility and uncertainty and/or a downturn in market and economic and financial conditions, as a result of

The Trustees/Directorsare responsible generally for overseeing the management of the Funds. The Trustees authorize the Funds to enter into service agreements with Pacific Investment Management Company LLC (“PIMCO”) and other service providers in order to provide, and in some cases authorize service providers to procure through other parties, necessary or desirable services on behalf of the Funds. Shareholders are not parties to or third-party beneficiaries of such service agreements. Neither a Fund’s prospectus or Statement of Additional Information (“SAI”), any press release or shareholder report, any contracts filed as exhibits to a Fund’s registration statement, nor any other communications, disclosure documents or regulatory filings (including this report) from or on behalf of a Fund creates a contract between or among any shareholders of a Fund, on the one hand, and the Fund, a service provider to the Fund, and/or the Trustees or officers of the Fund, on the other hand.

The Trustees (or the Funds and their officers, service providers or other delegates acting under authority of the Trustees) may amend its most recent prospectus or use a new prospectus or SAI with respect to a Fund, adopt and disclose new or amended policies and other changes in press releases and shareholder reports and/or amend, file and/or issue any other communications, disclosure documents or regulatory filings, and may amend or enter into any contracts to which a Fund is a party, and interpret the investment objective(s), policies, restrictions and contractual provisions applicable to any Fund, without shareholder input or approval, except in circumstances in which shareholder approval is specifically required by law (such as changes to fundamental investment policies) or where a shareholder approval requirement was specifically disclosed in a Fund’s then-current prospectus, SAI or shareholder report and is otherwise still in effect.

PIMCO has adopted written proxy voting policies and procedures (“Proxy Policy”) as required by Ruleunder the Investment Advisers Act of 1940, as amended. The Proxy Policy has been adopted by the Funds as the policies and procedures that PIMCO will use when voting proxies on behalf of the Funds. A description of the policies and procedures that PIMCO uses to vote proxies relating to portfolio securities of each Fund, and information about how each Fund voted proxies relating to portfolio securities held during the most recent twelve-month period ended June 30, are available without charge, upon request, by calling the Funds at (844)on the Funds’ website at www.pimco.com, and on the Securities and Exchange Commission’s (“SEC”) website at www.sec.gov.

The Funds file their complete schedules of portfolio holdings with the SEC for the first and third quarters of each fiscal year as an exhibit to their reports on Form N-PORT. The Funds’ Form N-PORT reports are available to the public on the SEC’s website at www.sec.gov and on PIMCO’s website at www.pimco.com, and upon request by calling PIMCO at (844) 33-PIMCO.

The following example illustrates the expenses that you would pay on a $1,000 investment in Common Shares of the Fund, assuming (1) that the Fund’s net assets do not increase or decrease, (2) that the Fund incurs total annual expenses of 6.13% of net assets attributable to Common Shares in years 1 through 10 (assuming assets attributable to reverse repurchase agreements representing 39.71% of the Fund’s total managed assets) and (3) a 5% annual return:

The following example illustrates the expenses that you would pay on a $1,000 investment in Common Shares of the Fund, assuming (1) that the Fund’s net assets do not increase or decrease, (2) that the Fund incurs total annual expenses of 6.63% of net assets attributable to Common Shares in years 1 through 10 (assuming assets attributable to reverse repurchase agreements representing 41.32% of the Fund’s total managed assets) and (3) a 5% annual return: