MAV Pioneer Municipal High Income Advantage Fund Inc

Notes to Financial Statements | 9/30/21

(unaudited)

1. Organization and Significant Accounting Policies

Pioneer Municipal High Income Advantage Fund, Inc. (the “Fund”) is organized as a Maryland corporation. Prior to April 21, 2021, the Fund was organized as a Delaware statutory trust. On April 21, 2021, the Fund redomiciled to a Maryland corporation through a statutory merger of the predecessor Delaware statutory trust with and into a newly-established Maryland corporation formed for the purpose of effecting the redomiciling. The Fund was originally organized on August 6, 2003. Prior to commencing operations on October 20, 2003, the Fund had no operations other than matters relating to its organization and registration as a diversified, closed-end management investment company under the Investment Company Act of 1940, as amended. The investment objective of the Fund is to seek a high level of current income exempt from regular federal income tax, and the Fund may, as a secondary objective, also seek capital appreciation to the extent that it is consistent with its primary investment objective.

Amundi Asset Management US, Inc., an indirect, wholly owned subsidiary of Amundi and Amundi’s wholly owned subsidiary, Amundi USA, Inc., serves as the Fund’s investment adviser (the “Adviser”). Prior to January 1, 2021, the Adviser was named Amundi Pioneer Asset Management, Inc.

In August 2018, the Financial Accounting Standards Board (FASB) issued Accounting Standards Update 2018-13 “Disclosure Framework - Changes to the Disclosure Requirements for Fair Value Measurement” (“ASU 2018-13”) which modifies disclosure requirements for fair value measurements, principally for Level 3 securities and transfers between levels of the fair value hierarchy. ASU 2018-13 is effective for fiscal years beginning after December 15, 2019 and for interim periods within those fiscal years. The Fund has adopted ASU 2018-13 for the six months ended September 30, 2021. The impact to the Fund’s adoption was limited to changes in the Fund’s disclosures regarding fair value, primarily those disclosures related to transfers between levels of the fair value hierarchy and disclosure of the range and weighted average used to develop significant unobservable inputs for Level 3 fair value investments, when applicable.

In March 2020, FASB issued an Accounting Standard Update, ASU 2020-04, Reference Rate Reform (Topic 848) — Facilitation of the Effects of Reference Rate Reform on Financial Reporting (“ASU 2020-04”), which provides optional, temporary relief with respect to the financial reporting of contracts subject to certain types of modifications due to the planned discontinuation of the London Interbank Offered Rate (“LIBOR”) and other

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LIBOR-based reference rates at the end of 2021. The temporary relief provided by ASU 2020-04 is effective for certain reference rate-related contract modifications that occur during the period from March 12, 2020 through December 31, 2022. Management is evaluating the impact of ASU 2020-04 on the Fund’s investments, derivatives, debt and other contracts, if applicable, that will undergo reference rate-related modifications as a result of the reference rate reform.

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

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

A. Security Valuation

The net asset value of the Fund is computed once daily, on each day the New York Stock Exchange (“NYSE”) is open, as of the close of regular trading on the NYSE.

Fixed-income securities are valued by using prices supplied by independent pricing services, which consider such factors as market prices, market events, quotations from one or more brokers, Treasury spreads, yields, maturities and ratings, or may use a pricing matrix or other fair value methods or techniques to provide an estimated value of the security or instrument. A pricing matrix is a means of valuing a debt security on the basis of current market prices for other debt securities, historical trading patterns in the market for fixed-income securities and/or other factors. Non-U.S. debt securities that are listed on an exchange will be valued at the bid price obtained from an independent third party pricing service. When independent third party pricing services are unable to supply prices, or when prices or market quotations are considered to be unreliable, the value of that security may be determined using quotations from one or more broker-dealers.

Securities for which independent pricing services or broker-dealers are unable to supply prices or for which market prices and/or quotations are not readily available or are considered to be unreliable are valued by a fair valuation team comprised of certain personnel of the Adviser pursuant to

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procedures adopted by the Fund’s Board of Directors. The Adviser’s fair valuation team uses fair value methods approved by the Valuation Committee of the Board of Directors. The Adviser’s fair valuation team is responsible for monitoring developments that may impact fair valued securities and for discussing and assessing fair values on an ongoing basis, and at least quarterly, with the Valuation Committee of the Board of Directors.

Inputs used when applying fair value methods to value a security may include credit ratings, the financial condition of the company, current market conditions and comparable securities. The Fund may use fair value methods if it is determined that a significant event has occurred after the close of the exchange or market on which the security trades and prior to the determination of the Fund’s net asset value. Examples of a significant event might include political or economic news, corporate restructurings, natural disasters, terrorist activity or trading halts. Thus, the valuation of the Fund’s securities may differ significantly from exchange prices, and such differences could be material.

At September 30, 2021, no securities were valued using fair value methods (other than securities valued using prices supplied by independent pricing services, broker-dealers or using a third party insurance industry pricing model).

B. Investment Income and Transactions

Interest income, including interest on income-bearing cash accounts, is recorded on the accrual basis. Dividend and interest income are reported net of unrecoverable foreign taxes withheld at the applicable country rates and net of income accrued on defaulted securities.

Discounts and premiums on purchase prices of debt securities are accreted or amortized, respectively, daily, into interest income on an effective yield to maturity basis with a corresponding increase or decrease in the cost basis of the security. Premiums and discounts related to certain mortgage-backed securities are amortized or accreted in proportion to the monthly paydowns.

Interest and dividend income payable by delivery of additional shares is reclassified as PIK (payment-in-kind) income upon receipt and is included in interest and dividend income, respectively.

Security transactions are recorded as of trade date. Gains and losses on sales of investments are calculated on the identified cost method for both financial reporting and federal income tax purposes.

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C. Federal Income Taxes

It is the Fund’s policy to comply with the requirements of the Internal Revenue Code applicable to regulated investment companies and to distribute all of its net taxable income and net realized capital gains, if any, to its shareowners. Therefore, no provision for federal income taxes is required. As of March 31, 2021, the Fund did not accrue any interest or penalties with respect to uncertain tax positions, which, if applicable, would be recorded as an income tax expense on the Statement of Operations. Tax returns filed within the prior three years remain subject to examination by federal and state tax authorities.

The amount and character of income and capital gain distributions to shareowners are determined in accordance with federal income tax rules, which may differ from U.S. GAAP. Distributions in excess of net investment income or net realized gains are temporary over distributions for financial statement purposes resulting from differences in the recognition or classification of income or distributions for financial statement and tax purposes. Capital accounts within the financial statements are adjusted for permanent book/tax differences to reflect tax character, but are not adjusted for temporary differences.

The tax character of current year distributions payable will be determined at the end of the current taxable year. The tax character of distributions paid during the year ended March 31, 2021 was as follows:

The following shows the components of distributable earnings (losses) on a federal income tax basis at March 31, 2021:

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The difference between book-basis and tax-basis unrealized appreciation/depreciation is primarily attributable to the book/tax differences in the accrual of income on securities in default, the difference between book and tax amortization methods and discounts on fixed income securities.

D. Automatic Dividend Reinvestment Plan

All shareowners whose shares are registered in their own names automatically participate in the Automatic Dividend Reinvestment Plan (the “Plan”), under which participants receive all dividends and capital gain distributions (collectively, dividends) in full and fractional shares of the Fund in lieu of cash. Shareowners may elect not to participate in the Plan. Shareowners not participating in the Plan receive all dividends and capital gain distributions in cash. Participation in the Plan is completely voluntary and may be terminated or resumed at any time without penalty by notifying American Stock Transfer & Trust Company, the agent for shareowners in administering the Plan (the “Plan Agent”), in writing prior to any dividend record date; otherwise such termination or resumption will be effective with respect to any subsequently declared dividend or other distribution.

If a shareowner’s shares are held in the name of a brokerage firm, bank or other nominee, the shareowner can ask the firm or nominee to participate in the Plan on the shareowner’s behalf. If the firm or nominee does not offer the Plan, dividends will be paid in cash to the shareowner of record. A firm or nominee may reinvest a shareowner’s cash dividends in shares of the Fund on terms that differ from the terms of the Plan.

Whenever the Fund declares a dividend on shares payable in cash, participants in the Plan will receive the equivalent in shares acquired by the Plan Agent either (i) through receipt of additional unissued but authorized shares from the Fund or (ii) by purchase of outstanding shares on the New York Stock Exchange or elsewhere. If, on the payment date for any dividend, the net asset value per share is equal to or less than the market price per share plus estimated brokerage trading fees (market premium), the Plan Agent will invest the dividend amount in newly issued shares. The number of newly issued shares to be credited to each account will be determined by dividing the dollar amount of the dividend by the net asset value per share on the date the shares are issued, provided that the maximum discount from the then current market price per share on the date of issuance does not exceed 5%. If, on the payment date for any dividend, the net asset value per share is greater than the market value (market discount), the Plan Agent will invest the dividend amount in

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shares acquired in open-market purchases. There are no brokerage charges with respect to newly issued shares. However, each participant will pay a pro rata share of brokerage trading fees incurred with respect to the Plan Agent’s open-market purchases. Participating in the Plan does not relieve shareowners from any federal, state or local taxes which may be due on dividends paid in any taxable year. Shareowners holding Plan shares in a brokerage account may be able to transfer the shares to another broker and continue to participate in the Plan.

E. Risks

The value of securities held by the Fund may go up or down, sometimes rapidly or unpredictably, due to general market conditions, such as real or perceived adverse economic, political or regulatory conditions, inflation, changes in interest rates, lack of liquidity in the bond markets or adverse investor sentiment. In the past several years, financial markets have experienced increased volatility, depressed valuations, decreased liquidity and heightened uncertainty. These conditions may continue, recur, worsen or spread.

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

The municipal bond market can be susceptible to unusual volatility, particularly for lower-rated and unrated securities. Liquidity can be reduced unpredictably in response to overall economic conditions or credit tightening. Municipal issuers may be adversely affected by rising health care costs, increasing unfunded pension liabilities, and by the phasing out of federal programs providing financial support. Unfavorable conditions and developments relating to projects financed with municipal securities can result in lower revenues to issuers of municipal securities, potentially resulting in defaults. Issuers often depend on revenues from these projects to make principal and interest payments. The value of municipal securities can also be adversely affected by changes in the financial condition of one or more individual municipal issuers or insurers of municipal issuers, regulatory and political developments, tax law changes or other legislative actions, and by uncertainties and public perceptions concerning these and other factors. Municipal securities may be more susceptible to down-grades or defaults during recessions or similar periods of economic stress. In recent periods, an increasing number of municipal issuers in the United States have defaulted on obligations and commenced insolvency proceedings. Financial difficulties of municipal issuers may continue or get worse. To the

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extent the Fund invests significantly in a single state, including Texas, New York and Massachusetts, or in securities the payments on which are dependent upon a single project or source of revenues, or that relate to a sector or industry, including health care facilities, education, transportation, special revenues and pollution control, the Fund will be more susceptible to associated risks and developments.

The Fund invests in below investment grade (high yield) municipal securities. Debt securities rated below investment grade are commonly referred to as “junk bonds” and are considered speculative. These securities involve greater risk of loss, are subject to greater price volatility, and are less liquid, especially during periods of economic uncertainty or change, than higher rated debt securities.

With the increased use of technologies such as the Internet to conduct business, the Fund is susceptible to operational, information security and related risks. While the Fund’s Adviser has established business continuity plans in the event of, and risk management systems to prevent, limit or mitigate, such cyber-attacks, there are inherent limitations in such plans and systems, including the possibility that certain risks have not been identified. Furthermore, the Fund cannot control the cybersecurity plans and systems put in place by service providers to the Fund such as the Fund’s custodian and accounting agent, and the Fund’s transfer agent. In addition, many beneficial owners of Fund shares hold them through accounts at broker-dealers, retirement platforms and other financial market participants over which neither the Fund nor the Adviser exercises control. Each of these may in turn rely on service providers to them, which are also subject to the risk of cyber-attacks. Cybersecurity failures or breaches at the Adviser or the Fund’s service providers or intermediaries have the ability to cause disruptions and impact business operations, potentially resulting in financial losses, interference with the Fund’s ability to calculate its net asset value, impediments to trading, the inability of Fund shareowners to effect share purchases or sales or receive distributions, loss of or unauthorized access to private shareowner information and violations of applicable privacy and other laws, regulatory fines, penalties, reputational damage, or additional compliance costs. Such costs and losses may not be covered under any insurance. In addition, maintaining vigilance against cyber-attacks may involve substantial costs over time, and system enhancements may themselves be subject to cyber-attacks.

COVID-19

The global pandemic of the novel coronavirus respiratory disease designated COVID-19 has resulted in major disruption to economies and markets around the world, including the United States. Global financial

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markets have experienced extreme volatility and severe losses, and trading in many instruments has been disrupted. Liquidity for many instruments has been greatly reduced for periods of time. Some interest rates are very low and in some cases yields are negative. Some sectors of the economy and individual issuers have experienced particularly large losses. Rates of inflation have recently risen. These circumstances may continue for an extended period of time, and may continue to affect adversely the value and liquidity of the Fund’s investments. Governments and central banks, including the Federal Reserve in the U.S., have taken extraordinary and unprecedented actions to support local and global economies and the financial markets. These actions have resulted in significant expansion of public debt, including in the U.S. The impact of these measures will not be known for some time. The consequences of high public debt, including its future impact on the economy and securities markets, likewise may not be known for some time.

F. Restricted Securities

Restricted Securities are subject to legal or contractual restrictions on resale. Restricted securities generally are resold in transactions exempt from registration under the Securities Act of 1933. Private placement securities are generally considered to be restricted except for those securities traded between qualified institutional investors under the provisions of Rule 144A of the Securities Act of 1933. Disposal of restricted investments may involve negotiations and expenses, and prompt sale at an acceptable price may be difficult to achieve. Restricted investments held by the Fund at September 30, 2021 are listed in the Schedule of Investments.

G. Statement of Cash Flows

Information on financial transactions which have been settled through the receipt or disbursement of cash or restricted cash is presented in the Statement of Cash Flows. Cash as presented in the Fund’s Statement of Assets and Liabilities includes cash on hand at the Fund’s custodian bank and does not include any short-term investments. As of and for the six months ended September 30, 2021, the Fund had no restricted cash presented on the Statement of Assets and Liabilities.

2. Management Agreement

The Adviser manages the Fund’s portfolio. Management fees payable under the Fund’s Investment Management with the Adviser are calculated daily and paid monthly at the annual rate of 0.60% of the Fund’s average daily managed assets. “Managed assets” means (a) the total assets of the Fund,

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including any form of investment leverage, minus (b) all accrued liabilities incurred in the normal course of operations, which shall not include any liabilities or obligations attributable to investment leverage obtained through (i) indebtedness of any type (including, without limitation, borrowing through a credit facility or the issuance of debt securities), (ii) the issuance of preferred stock or other similar preference securities, and/or (iii) any other means. For the six months ended September 30, 2021, the net management fee was 0.61% (annualized) of the Fund’s average daily managed assets, which was equivalent to 0.97% (annualized) of the Fund’s average daily net assets.

In addition, under the management and administration agreements, certain other services and costs, including accounting, regulatory reporting and insurance premiums, are paid by the Fund as administrative reimbursements. Included in “Due to affiliates” reflected on the Statement of Assets and Liabilities is $16,880 in management fees, administrative costs and certain other reimbursements payable to the Adviser at September 30, 2021.

3. Compensation of Directors and Officers

The Fund pays an annual fee to its Directors. The Adviser reimburses the Fund for fees paid to the Interested Directors. The Fund does not pay any salary or other compensation to its officers. For the six months ended September 30, 2021, the Fund paid $9,129 in Directors’ compensation, which is reflected on the Statement of Operations as Directors’ fees. At September  30, 2021, the Fund had a payable for Directors’ fees on its Statement of Assets and Liabilities of $2,491.

4. Transfer Agent

American Stock Transfer & Trust Company serves as the transfer agent with respect to the Fund's shares. The Fund pays AST an annual fee as is agreed to from time to time by the Fund and AST for providing such services.

In addition, the Fund reimbursed the transfer agent for out-of-pocket expenses incurred by the transfer agent related to shareowner communications activities such as proxy and statement mailings, and outgoing phone calls.

5. Fund Shares

There are 1,000,000,000 shares of common stock of the Fund (“common shares”), $0.001 par value per share authorized.

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Transactions in common shares for the six months ended September 30, 2021 and year ended March 31, 2021 were as follows:

The Fund may classify or reclassify any unissued shares into one or more series of preferred shares.

As of September 30, 2021, the Fund has outstanding 1,800 Variable Rate MuniFund Term Preferred Shares Series 2021 (“series 2021 VMTP Shares” or “VMTP Shares”). The Fund issued 1,600 VMTP Shares on February 16, 2018 and 200 VMTP Shares on February 16, 2021. See Note 6 for additional information.

Prior to February 16, 2018, the Fund had outstanding 3,000 Series A APS and 3,000 Series B APS. The Fund mailed a notice of redemption and deposited funds sufficient to redeem the APS with the auction agent on February 16, 2018. The Fund redeemed all outstanding Series A APS and Series B APS on February 20, 2018.

6. Variable Rate MuniFund Term Preferred Shares

The Fund has 1,800 shares issued and outstanding of Series 2021 VMTP Shares, with a liquidation preference of $100,000 per share. VMTP Shares are issued via private placement and are not publicly available.

The Fund is obligated to redeem its VMTP Shares by the date as specified in its offering document (“Term Redemption Date”), unless earlier redeemed by the Fund. VMTP Shares are subject to optional and mandatory redemption in certain circumstances. The VMTP Shares may be redeemed at the option of the Fund, subject to payment of premium for approximately one year following the date of issuance (“Optional Redemption Date”), and at the redemption price per share thereafter. The redemption price per share is equal to the sum of the liquidation preference per share plus any accumulated but unpaid dividends. The Fund may be obligated to redeem a certain amount of the VMTP Shares if it fails to maintain certain asset coverage and leverage ratio requirements and such failures are not cured by the applicable cure date. The Term Redemption Date for the Fund’s Series 2021 VMT Shares was extended from August 2, 2021 to August 2, 2024 in February 2021. Six months prior to Term Redemption Date, the Fund is required to segregate liquid assets with the Fund’s custodian in an amount equal to at least 100% of the term redemption amount.

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VMTP Shares are subject to restrictions on transfer, generally do not trade, and market quotations are generally not available. VMTP Shares are short-term or short/intermediate-term instruments that pay a variable dividend rate tied to a short-term index, plus an additional fixed “spread” amount established at the time of issuance. For financial reporting purposes, the liquidation preference of VMTP Shares is a liability and is recognized as a component of “Variable Rate MuniFund Term Preferred Shares” on the Statement of Assets and Liabilities since the shares have a stated mandatory redemption date.

Dividends on the VMTP Shares (which are treated as interest payments for financial reporting purposes and are recorded as interest expense on the Statement of Operations) are declared daily, paid monthly and recorded as incurred. For the six months ended September 30, 2021, interest expense on VMTP Shares amounted to $785,000. The dividend rate for the VMTP Shares is determined weekly. Unpaid dividends on VMTP Shares are recognized as “Interest Expense Payable” on the Statement of Assets and Liabilities. For the six months ended September 30, 2021, interest expense payable on VMTP Shares amounted to $78. From April 1, 2020 through September 30, 2021, the Series 2021 VMTP Shares paid an average dividend rate of 0.88% and the average liquidation value outstanding of VMTP Shares for the Fund during the six months ended September 30, 2021, was $180,000,000.

The Fund did not incur any offering costs as a result of the offerings on February 16, 2018 and February 16, 2021.

Transactions in the Series 2021 VMTP Shares during the Fund’s current and prior reporting periods were as follows:

7. Redomiciling

On April 21, 2021, the Fund, previously organized as a Delaware statutory trust, redomiciled to a Maryland corporation (the “redomiciling”). The redomiciling was effected through a statutory merger of the predecessor Delaware statutory trust (the “Predecessor Entity”) with and into a newly-established Maryland corporation formed for the purpose of effecting the

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redomiciling (the “Successor Entity”) pursuant to the terms of an

Agreement and Plan of Merger entered into by and between the Predecessor Entity and the Successor Entity (the “Merger”). Upon effectiveness of the Merger, (i) the Successor Entity became the successor in interest to the Fund, (ii) each outstanding share of common stock of the Predecessor Entity was automatically converted into one share of common stock of the Successor Entity, (iii) each outstanding VMTP Share of the Predecessor Entity was automatically converted into one VMTP Share of the Successor Entity, and (iv) the shareholders of the Predecessor Entity became stockholders of the Successor Entity. Neither the Fund nor its stockholders realized gain (loss) as a direct result of the Merger. Accordingly, the Merger had no effect on the Fund’s operations.

In connection with the redomiciling, the Fund’s name changed from Pioneer Municipal High Income Trust to Pioneer Municipal High Income Fund, Inc. The Fund’s ticker symbol on the New York Stock Exchange did not change.

The redomiciling did not result in any change to the investment adviser, investment objective and strategies, portfolio management team, policies and procedures or the members of the Board overseeing the Fund.

Following the Fund’s redomiciling, the rights of shareholders are governed by Maryland General Corporation Law and the Articles of Incorporation and Bylaws of the Successor Entity. In addition, the Fund is subject to the Maryland Control Share Acquisition Act (the “Control Share Act”) following the redomiciling.

The Control Share Act generally provides that any holder of “control shares” acquired in a “control share acquisition” may not exercise voting rights with respect to the “control shares,” except to the extent approved by a vote of two-thirds of all the votes entitled to be cast on the matter. Generally, “control shares” are shares that, when aggregated with shares already owned by an acquiring person, would entitle the acquiring person to exercise 10% or more, 33 1/3% or more, or a majority of the total voting power of shares entitled to vote in the election of directors. The Control Share Act provides that a “control share acquisition” does not include the acquisition of shares in a merger, consolidation or share exchange. Therefore, a shareholder of the Fund that acquired shares of the Successor Entity as a result of the Merger will be able to exercise voting rights as to those shares even if the number of such shares acquired by the shareholder in the Merger exceeds one or more of the thresholds of the Control Share Act.

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The above description of the Control Share Act is only a high-level summary and does not purport to be complete. Investors should refer to the actual provisions of the Control Share Act and the Fund’s Bylaws for more information, including definitions of key terms, various exclusions and exemptions from the statute’s scope, and the procedures by which stockholders may approve the reinstatement of voting rights to holders of “control shares.”

8. Subsequent Events

A monthly dividend was declared on October 5, 2021 from undistributed and accumulated net investment income of $ 0.0400 per common share payable October 29, 2021, to common shareowners of record on October 19, 2021.

Subsequent to September 30, 2021, dividends declared and paid on VMTP Shares totaled $131,390 through October 31, 2021.

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Additional Information