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The Fund may offer and sell up to 10,000,000 of its Common Shares, $0.01 par value per share, from time to time through Virtu Americas, as sub-placement agent under this Prospectus Supplement and the accompanying prospectus. The following table sets forth the Fund’s capitalization (1) on a historical basis as of June 10, 2026; and (2) on a pro forma basis as adjusted to reflect the assumed sale of 10,000,000 Common Shares at $14.31 per share (the last reported price per share of the Common Shares on the NYSE on June 10, 2026), in an offering under this Prospectus Supplement and the accompanying prospectus, after deducting the assumed commission of $1,431,000 (representing an estimated commission to Nuveen Securities of 1.00% of the gross proceeds of the sale of Common Shares), out of which Nuveen Securities will compensate Virtu Americas, at a rate of up to 0.80% of the gross sales proceeds of the sale of the Common Shares sold by Virtu Americas. There is no guarantee that there will be any sales of the Common Shares pursuant to this Prospectus Supplement and the accompanying prospectus. Actual sales, if any, of the Common Shares under this Prospectus Supplement and the accompanying prospectus may be greater or less than $14.31 per share, depending on the market price of the Common Shares at the time of any such sale.

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TRADING AND NET ASSET VALUE INFORMATION

The following table shows for the periods indicated: (i) the high and low sales prices for the Common Shares reported as of the end of the day on the NYSE, (ii) the corresponding NAV per share, and (iii) the premium/(discount) to NAV per share at which the Common Shares were trading as of such date. The Fund’s Common Shares have historically traded both at premiums and discounts in relation to the Fund’s NAV per share. The Fund cannot predict whether its Common Shares will trade at a premium or discount to NAV in the future. The Board of Trustees has currently determined that, at least annually, it will consider action that might be taken to reduce or eliminate any material discount from NAV in respect of Common Shares, which may include the repurchase of such shares in the open market or in private transactions, the making of a tender offer for such shares at NAV, or the conversion of the Fund to an open-end investment company. The Fund cannot assure you that its Board of Trustees will decide to take any of these actions, or that share repurchases or tender offers will actually reduce market discount.

The net asset value per Common Share, the market price, and percentage of premium/(discount) to net asset value per Common Share on June 10, 2026, was $14.34, $14.31 and (0.21)%, respectively. As of June 10, 2026, the Fund had 62,951,599 Common Shares outstanding and net assets applicable to Common Shares of $902,876,351.

THE FUND

The Fund is a diversified, closed-end management investment company registered under the 1940 Act. The Fund was organized as a Massachusetts business trust on January 29, 1992. The Fund’s Common Shares are listed on the NYSE under the symbol “NXP.” Rights issued by the Fund may also be listed on a securities exchange.

The following provides information about the Fund’s outstanding Common Shares as of June 10, 2026:

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USE OF PROCEEDS

Unless otherwise specified in a prospectus supplement, the net proceeds from any offering will be invested in accordance with the Fund’s investment objective and policies as stated below. The Fund currently anticipates that it will be able to invest substantially all of the net proceeds in investments that meet the Fund’s investment objective and policies within approximately three months of the receipt of such proceeds. Pending investment, it is anticipated that the proceeds will be invested in short-term or long-term securities issued by the U.S. Government and its agencies or instrumentalities or in high-quality, short-term money market instruments.

THE FUND’S INVESTMENTS

Investment Objective and Policies

Please refer to the section of the Fund’s most recent annual report on Form N-CSR entitled “Shareholder Update—Current Investment Objectives, Investment Policies and Principal Risks of the Funds—Investment Objective” and “—Investment Policies,” as such investment objective and investment policies may be supplemented from time to time, which is incorporated by reference herein, for a discussion of the Fund’s investment objective and policies.

Portfolio Composition and Other Information

Please refer to the section of the Fund’s most recent annual report on Form N-CSR entitled “Shareholder Update—Current Investment Objectives, Investment Policies and Principal Risks of the Funds—Investment Policies—Portfolio Contents,” as such portfolio contents may be supplemented from time to time, which is incorporated by reference herein, for a discussion of the investments principally included in the Fund’s portfolio. More detailed information about the Fund’s portfolio investments are contained in the SAI under “The Fund’s Investments.”

Portfolio Turnover

The Fund may engage in portfolio trading when considered appropriate, but short-term trading will not be used as the primary means of achieving the Fund’s investment objective. For the fiscal year ended March 31, 2026, the Fund’s portfolio turnover rate was 22%. However, there are no limits on the Fund’s rate of portfolio turnover, and investments may be sold without regard to length of time held when, in Nuveen Asset Management’s opinion, investment considerations warrant such action. A higher portfolio turnover rate would result in correspondingly greater brokerage commissions and other transactional expenses that are borne by the Fund. Although these commissions and expenses are not reflected in the Fund’s “Annual Expenses,” they will be reflected in the Fund’s total return. In addition, high portfolio turnover may result in the realization of net short-term capital gains by the Fund which, when distributed to shareholders, will be taxable as ordinary income. See “Tax Matters.”

Other Policies

Certain investment policies specifically identified in the SAI as such are considered fundamental and may not be changed without shareholder approval. See “Investment Restrictions” in the SAI.

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USE OF LEVERAGE

As a fundamental policy, the Fund will not leverage its capital structure by issuing "senior securities" (as defined under the 1940 Act), such as preferred shares or debt instruments. However, the Fund may borrow (which may include reverse repurchase agreements) for temporary or emergency purposes or for repurchase of its shares as permitted by the 1940 Act, and use certain derivatives and other financing instruments, including inverse floating rate securities, that have the economic effect of leverage by creating additional investment exposures.

The Fund also may borrow for temporary or emergency purposes as permitted by the 1940 Act. The Fund, along with certain other funds managed by Nuveen Fund Advisors (the “Participating Funds”), are parties to a committed unsecured credit facility (the “Facility”) provided by a group of lenders, under which Participating Funds may borrow for temporary purposes only. Outstanding balances drawn by the Fund, or any other Participating Fund, will bear interest at a variable rate and is the liability of such Fund. The Facility is not intended for sustained levered investment purposes. A large portion of the Facility’s capacity (and corresponding annual costs, excluding interest cost) is currently allocated by Nuveen Fund Advisors to a small number of Participating Funds, which does not include the Fund. The Facility has a 364-day term and will expire in June 2027 unless extended or renewed. Because participation in the Facility creates a conflict of interest in determining which Participating Funds may draw upon the Facility at any point in time, Participating Funds have been allocated different first priority portions of the committed amount of the Facility based primarily on the expected likelihood and extent of the need to borrow under the Facility.  

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RISK FACTORS

Risk is inherent in all investing. Investing in any investment company security involves risk, including the risk that you may receive little or no return on your investment or even that you may lose part or all of your investment. Please refer to the section of the Fund’s most recent annual report on Form N-CSR entitled “Shareholder Update—Current Investment Objectives, Investment Policies and Principal Risks of the Funds—Principal Risks of the Funds,” as such principal risks may be supplemented from time to time, which is incorporated by reference herein, for a discussion of the principal risks you should consider before making an investment in the Fund. Any additional risks applicable to a particular offering of Securities will be set forth in the related prospectus supplement.

MANAGEMENT OF THE FUND

Trustees and Officers

The Board of Trustees is responsible for the management of the Fund, including supervision of the duties performed by Nuveen Fund Advisors and Nuveen Asset Management. The names and business addresses of the trustees and officers of the Fund and their principal occupations and other affiliations during the past five years are set forth under “Management of the Fund” in the SAI.

Investment Adviser, Sub-Adviser and Portfolio Managers

Investment Adviser. Nuveen Fund Advisors, LLC, the Fund’s investment adviser, is responsible for overseeing the Fund’s overall investment strategy and implementation. Nuveen Fund Advisors offers advisory and investment management services to a broad range of investment company clients. Nuveen Fund Advisors has overall responsibility for management of the Fund, oversees the management of the Fund’s portfolio, manages the Fund’s business affairs and provides certain clerical, bookkeeping and other administrative services. Nuveen Fund Advisors is located at 333 West Wacker Drive, Chicago, Illinois 60606. Nuveen Fund Advisors is an indirect subsidiary of Nuveen, the investment management arm of TIAA. TIAA is a life insurance company founded in 1918 by the Carnegie Foundation for the Advancement of Teaching and is the companion organization of College Retirement Equities Fund. As of March 31, 2026, Nuveen managed approximately $1.4 trillion in assets, of which approximately $157.2 billion was managed by Nuveen Fund Advisors.

Sub-Adviser. Nuveen Asset Management, LLC, located at 333 West Wacker Drive, Chicago, Illinois 60606, serves as the Fund’s sub-adviser pursuant to a sub-advisory agreement between Nuveen Fund Advisors and Nuveen Asset Management (the “Sub-Advisory Agreement”). Nuveen Asset Management, a registered investment adviser, is a wholly owned subsidiary of Nuveen Fund Advisors. Nuveen Asset Management oversees day-to-day investment operations of the Fund. Pursuant to the Sub-Advisory Agreement, Nuveen Asset Management is compensated for the services it provides to the Fund with a portion of the management fee Nuveen Fund Advisors receives from the Fund. Nuveen Fund Advisors and Nuveen Asset Management retain the right to reallocate investment advisory responsibilities and fees between themselves in the future.

Portfolio Managers. Nuveen Asset Management is responsible for the execution of specific investment strategies and day-to-day investment operations of the Fund. Nuveen Asset Management manages the Nuveen funds using a team of analysts and portfolio managers that focuses on a specific group of funds. The day-to-day operation of the Fund and the execution of its specific investment strategies is the primary responsibility of Michael S. Hamilton and Stephen J. Candido, CFA, the designated portfolio managers of the Fund. Mr. Hamilton has served as portfolio manager of the Fund since 2016 and Mr. Candido has served as portfolio manager of the Fund since August 2023. 

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Michael S. Hamilton, Managing Director and Portfolio Manager at Nuveen Asset Management, manages tax-exempt fixed income portfolios. He began working in the investment industry when he joined the firm in 1989. He became a portfolio manager in 1992, and was previously a fixed income fund manager and trader. Mr. Hamilton graduated with a B.A. from the College of Idaho and an M.B.A. from Western Washington University. Mr. Hamilton is a member of the CFA Institute and Portland Society of Financial Analysts. 

Stephen J. Candido, CFA, Managing Director at Nuveen Asset Management, is a portfolio manager for high yield municipal strategies at Nuveen, managing high yield funds and institutional accounts. He also has responsibility for tax-exempt open-end funds and closed-end funds that allocate to both investment grade and high yield municipals. Stephen started working in the investment industry in 1996 when he joined Nuveen in the unit trust division. Prior to his current role, he was a vice president and senior research analyst specializing in high yield sectors including land secured credits, project finance and housing. Stephen was also an assistant vice president for Nuveen’s global structured products team beginning in 2005. He also served as the manager of the fixed income unit trust product management and pricing group starting in 2001 and prior to that held positions as an equity research analyst and fixed income pricing analyst. Stephen graduated with a B.S. in Finance from Miami University and an M.B.A. in Finance from the University of Illinois at Chicago. He holds the Chartered Financial Analyst designation and is a member of the CFA Institute and the CFA Society of Chicago. 

Additional information about the Portfolio Managers’ compensation, other accounts managed by the Portfolio Managers and the Portfolio Managers’ ownership of securities in the Fund is provided in the SAI. The SAI is available free of charge by calling (800) 257-8787 or by visiting the Fund’s website at www.nuveen.com. The information contained in, or that can be accessed through, the Fund’s website is not part of this Prospectus or the SAI, except to the extent specifically incorporated by reference herein or in the SAI.

Investment Management and Sub-Advisory Agreements

Investment Management Agreement. Pursuant to an investment management agreement between Nuveen Fund Advisors and the Fund (the “Investment Management Agreement”), the Fund has agreed to pay an annual management fee for the services and facilities provided by Nuveen Fund Advisors, payable on a monthly basis, based on the sum of a fund-level fee and a complex-level fee, as described below.

Fund-Level Fee. The annual fund-level fee for the Fund, payable monthly, is calculated according to the following schedule:

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Complex-Level Fee. The overall complex-level fee, payable monthly, begins at a maximum rate of 0.1600% of the Fund’s average daily managed assets, with breakpoints for eligible complex-level assets above $124.3 billion. Therefore, the maximum management fee rate for the Fund is the Fund-level fee plus 0.1600%. The current overall complex-level fee schedule is as follows:

As of May 31, 2026, the complex-level fee rate for the Fund was 0.1545%.

In addition to the fee of Nuveen Fund Advisors, the Fund pays all other costs and expenses of its operations, including compensation of its trustees (other than those affiliated with Nuveen Fund Advisors and Nuveen Asset Management), custodian, transfer agency and dividend disbursing expenses, legal fees, expenses of independent auditors, expenses of repurchasing shares, expenses associated with any borrowings, expenses of preparing, printing and distributing shareholder reports, notices, proxy statements and reports to governmental agencies, and taxes, if any. All fees and expenses are accrued daily and deducted before payment of dividends to investors.

A discussion regarding the basis for the Board of Trustees’ most recent approval of the Investment Management Agreement for the Fund may be found in the Fund’s semi-annual report to shareholders dated September 30, 2025.

Sub-Advisory Agreement. Pursuant to the Sub-Advisory Agreement, Nuveen Asset Management receives from Nuveen Fund Advisors a management fee equal to 60.0000% of Nuveen Fund Advisors’ net management fee from the Fund. Nuveen Fund Advisors and Nuveen Asset Management retain the right to reallocate investment advisory responsibilities and fees between themselves in the future.

A discussion regarding the basis for the Board of Trustees’ most recent approval of the Sub-Advisory Agreement for the Fund may be found in the Fund’s semi-annual report to shareholders dated September 30, 2025.

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Control Persons and Principal Holders of Common Shares

As of June 1, 2026, no shareholders owned of record, or were known by the Fund to own of record or beneficially, five percent or more of any class of shares of the Fund.

NET ASSET VALUE

The Fund’s NAV per Common Share is determined as of the close of trading (normally 4:00 p.m. Eastern time) on each day the NYSE is open for business. NAV is calculated by taking the market value of the Fund’s total assets, less all liabilities, and dividing by the total number of Common Shares outstanding. The result, rounded to the nearest cent, is the NAV per share.

The Fund utilizes independent pricing services approved by its valuation designee to value portfolio instruments at their market value. Independent pricing services typically value non-equity portfolio instruments utilizing a range of market-based inputs and assumptions, including market quotations obtained from broker-dealers making markets in such instruments, cash flows and transactions for comparable instruments. In valuing municipal securities, the pricing services may also consider, among other factors, the yields or prices of municipal securities of comparable quality, type of issue, coupon, maturity and rating and the obligor’s credit characteristics considered relevant by the pricing service or Nuveen Fund Advisors. In pricing certain securities, particularly less liquid and lower quality securities, the pricing services may consider information about a security, its issuer or market activity provided by Nuveen Fund Advisors or Nuveen Asset Management.

If a price cannot be obtained from a pricing service or other pre-approved source, or if the Fund’s valuation designee deems such price to be unreliable, or if a significant event occurs after the close of the local market but prior to the time at which the Fund’s NAV is calculated, a portfolio instrument will be valued at its fair value as determined in good faith by the Fund’s valuation designee. The Fund’s valuation designee may determine that a price is unreliable in various circumstances. For example, a price may be deemed unreliable if it has not changed for an identified period of time, or has changed from the previous day’s price by more than a threshold amount, and recent transactions and/or broker dealer price quotations differ materially from the price in question.

The Board of Trustees has designated Nuveen Fund Advisors as the Fund’s valuation designee pursuant to Rule 2a-5 under the 1940 Act and delegated to Nuveen Fund Advisors the day-to-day responsibility of making fair value determinations. All fair value determinations made by Nuveen Fund Advisors are subject to review by the Board of Trustees. As a general principle, the fair value of a portfolio instrument is the amount that an owner might reasonably expect to receive upon the instrument’s current sale. A range of factors and analysis may be considered when determining fair value, including relevant market data, interest rates, credit considerations and/or issuer specific news. However, fair valuation involves subjective judgments, and it is possible that the fair value determined for a portfolio instrument may be materially different from the value that could be realized upon the sale of that instrument.

DISTRIBUTIONS

The Fund pays regular monthly cash distributions to Common Shareholders (stated in terms of a fixed cents per Common Share dividend distribution rate which may be set from time to time). The Fund intends to distribute all or substantially all of its net investment income each year through its regular monthly distributions and to distribute realized capital gains at least annually. In addition, in any monthly period, to maintain its declared per common share distribution amount, the Fund may distribute more or less than its net investment income during the period. In the event the Fund distributes more than its net investment income during any yearly period, such distributions may also include realized gains and/or a return of capital. A return of capital is a non-taxable distribution of a portion of the Fund's capital. When the Fund returns exceed distributions, return of capital may represent portfolio gains earned, but not realized as a taxable capital gain. In periods when the Fund returns fall short of distributions, it will represent a portion of a shareholder's original principal unless the shortfall is offset during other time periods over the life of their investment (previous or subsequent) when the Fund's total return exceeds distributions. A return of capital reduces a shareholder's tax cost basis (but not below zero) in Fund shares, which would result in more taxable gain or less taxable loss when the shareholder sells their shares. Distributions in excess of a shareholder's tax basis in their shares is taxable as capital gains, long-term if the shares have been held for more than one year.

To the extent that a distribution includes a return of capital the NAV per share may erode. A return of capital may occur, for example, when some or all of the money that you invested in the Fund is paid back to you. A return of capital distribution does not necessarily reflect the Fund’s investment performance and should not be confused with “yield” or “income.”

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If the Fund’s distribution includes anything other than net investment income, the Fund will provide a notice to Common Shareholders of its best estimate of the distribution sources at the time of the distribution. These estimates may not match the final tax characterization (for the full year’s distributions) contained in the Common Shareholders’ 1099-DIV forms after the end of the year.

While the Fund intends to distribute all realized capital gains at least annually, the Fund may elect to retain all or a portion of any net capital gain (which is the excess of net long-term capital gain over net short-term capital loss) otherwise allocable to Common Shareholders and pay U.S. federal income tax on the retained gain. As provided under U.S. federal income tax law, Common Shareholders of record as of the end of the Fund’s taxable year will include their share of the retained net capital gain in their income for the year as a long-term capital gain (regardless of their holding period in the common shares), and will be entitled to an income tax credit or refund for the federal income tax deemed paid on their behalf by the Fund. If the Fund’s total distributions during a given year is an amount that exceeds the Fund’s current and accumulated earnings and profits, the excess would be treated by Common Shareholders as return of capital for federal income tax purposes to the extent of the Common Shareholder’s basis in their shares and thereafter as capital gain.

Distributions will be reinvested in additional shares under the Fund’s Dividend Reinvestment Plan unless a shareholder elects to receive cash. The Fund reserves the right to change its distribution policy and the basis for establishing the rate of its monthly distributions at any time and may do so without prior notice to Common Shareholders.

DIVIDEND REINVESTMENT PLAN

Please refer to the section of the Fund’s most recent annual report on Form N-CSR entitled “Shareholder Update—Dividend Reinvestment Plan,” which is incorporated by reference herein, for a discussion of the Fund’s dividend reinvestment plan.

PLAN OF DISTRIBUTION

The Fund may offer and sell Securities from time to time on an immediate, continuous or delayed basis, in one or more offerings under this Prospectus and a related prospectus supplement, on terms to be determined at the time of the offering. The Fund may offer and sell such Securities directly to one or more purchasers, to or through underwriters, through dealers or agents that the Fund designates from time to time, or through a combination of these methods. Sales of Securities may be made in transactions that are deemed to be “at the market” as defined in Rule 415 under the Securities Act of 1933, as amended (the “1933 Act”), including sales made directly on the NYSE or sales made to or through a market maker other than on an exchange.

The prospectus supplement relating to any offering of Securities will describe the terms of such offering, including, as applicable:

The prospectus supplement relating to any Rights offering will set forth the number of Common Shares issuable upon the exercise of each Right (or number of Rights) and the other terms of such Rights offering.

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Direct Sales

The Fund may offer and sell Securities directly to, and solicit offers from, institutional investors or others who may be deemed to be underwriters as defined in the 1933 Act for any resales of Securities. In this case, no underwriters or agents would be involved. The Fund may use electronic media, including the Internet, to sell offered Securities directly. The Fund will describe the terms of any of those sales in a prospectus supplement.

By Agents

The Fund may offer and sell Securities through an agent or agents designated by the Fund from time to time. An agent may sell Securities it has purchased from the Fund as principal to other dealers for resale to investors and other purchasers, and may reallow all or any portion of the discount received in connection with the purchase from the Fund to the dealers. After the initial offering of Securities, the offering price (in the case of Securities to be resold at a fixed offering price), the concession and the discount may be changed.

By Underwriters

If any underwriters are involved in the offer and sale of Securities, such Securities will be acquired by the underwriters and may be resold by them, either at a fixed public offering price established at the time of offering or from time to time in one or more negotiated transactions or otherwise, at prices related to prevailing market prices determined at the time of sale. Unless otherwise set forth in the applicable prospectus supplement, the obligations of the underwriters to purchase Securities will be subject to conditions precedent and the underwriters will be obligated to purchase all Securities described in the prospectus supplement if any are purchased. Any initial public offering price and any discounts or concessions allowed or re-allowed or paid to underwriters may be changed from time to time.

In connection with an offering of Common Shares, if a prospectus supplement so indicates, the Fund may grant the underwriters an option to purchase additional Common Shares at the public offering price, less the underwriting discounts and commissions, within 45 days from the date of the prospectus supplement, to cover any overallotments.

By Dealers

The Fund may offer and sell Securities from time to time through one or more dealers who would purchase the securities as principal. The dealers then may resell the offered Securities to the public at fixed or varying prices to be determined by those dealers at the time of resale. The Fund will set forth the names of the dealers and the terms of the transaction in the prospectus supplement.

General

Any underwriters, dealer or agent participating in an offering of Securities may be deemed to be an “underwriter,” as that term is defined in the 1933 Act, of Securities so offered and sold, and any discounts and commission received by them, and any profit realized by them on resale of the offered Securities for whom they act as agent, may be deemed to be underwriting discounts and commissions under the 1933 Act.

Underwriters, dealers and agents may be entitled, under agreements entered into with the Fund, to indemnification by the Fund against some liabilities, including liabilities under the 1933 Act.

The Fund may offer to sell Securities either at a fixed price or at prices that may vary, at market prices prevailing at the time of sale, at prices related to prevailing market prices or at negotiated prices.

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To facilitate an offering of Common Shares in an underwritten transaction and in accordance with industry practice, the underwriters may engage in transactions that stabilize, maintain, or otherwise affect the market price of the Common Shares or any other Security. Those transactions may include overallotment, entering stabilizing bids, effecting syndicate covering transactions, and reclaiming selling concessions allowed to an underwriter or a dealer.

Any of these activities may stabilize or maintain the market price of the Securities above independent market levels. Underwriters are not required to engage in these activities and may end any of these activities at any time.

In connection with any Rights offering, the Fund may also enter into a standby underwriting arrangement with one or more underwriters pursuant to which the underwriter(s) will purchase Common Shares remaining unsubscribed for after the Rights offering.

Underwriters, agents and dealers may engage in transactions with or perform services, including various investment banking and other services, for the Fund and/or any of the Fund’s affiliates in the ordinary course of business.

The maximum amount of compensation to be received by any Financial Industry Regulatory Authority (“FINRA”) member or independent broker-dealer will not exceed the applicable FINRA limit for the sale of any securities being offered pursuant to Rule 415 under the Securities Act. We will not pay any compensation to any underwriter or agent in the form of warrants, options, consulting or structuring fees or similar arrangements.

To the extent permitted under the 1940 Act and the rules and regulations promulgated thereunder, the underwriters may from time to time act as a broker or dealer and receive fees in connection with the execution of the Fund’s portfolio transactions after the underwriters have ceased to be underwriters and, subject to certain restrictions, each may act as a broker while it is an underwriter.

A prospectus and accompanying prospectus supplement in electronic form may be made available on the websites maintained by underwriters. The underwriters may agree to allocate a number of Securities for sale to their online brokerage account holders. Such allocations of Securities for Internet distributions will be made on the same basis as other allocations. In addition, Securities may be sold by the underwriters to securities dealers who resell Securities to online brokerage account holders.

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DESCRIPTION OF SHARES

Common Shares

The Declaration of Trust authorizes the issuance of an unlimited number of Common Shares. The Common Shares being offered have a par value of $0.01 per share and, subject to the rights of holders of borrowings, if incurred, have equal rights to the payment of dividends and the distribution of assets upon liquidation of the Fund. The Common Shares being offered will, when issued, be fully paid and, subject to matters discussed under “Certain Provisions in the Declaration of Trust and By-Laws,” non-assessable, and will have no preemptive or conversion rights or rights to cumulative voting. Each whole Common Share has one vote with respect to matters upon which a shareholder vote is required, and each fractional share shall be entitled to a proportional fractional vote consistent with the requirements of the 1940 Act and the rules promulgated thereunder, and will vote together as a single class. Whenever the Fund incurs borrowings, Common Shareholders will not be entitled to receive any cash distributions from the Fund unless all interest on such borrowings has been paid, unless asset coverage (as defined in the 1940 Act) with respect to any borrowings would be at least 300% after giving effect to the distributions.

The Common Shares are listed on the NYSE and trade under the ticker symbol “NXP.” The Fund intends to hold annual meetings of shareholders so long as the Common Shares are listed on a national securities exchange and such meetings are required as a condition to such listing. The Fund does not issue share certificates.

Unlike open-end funds, closed-end funds like the Fund do not provide daily redemptions. Rather, if a shareholder determines to buy additional Common Shares or sell shares already held, the shareholder may conveniently do so by trading on the exchange through a broker or otherwise. Common shares of closed-end investment companies may frequently trade on an exchange at prices lower than NAV. Common shares of closed-end investment companies like the Fund have during some periods traded at prices higher than NAV and have during other periods traded at prices lower than NAV.

Because the market value of the Common Shares may be influenced by such factors as distribution levels (which are in turn affected by expenses), call protection, dividend stability, portfolio credit quality, NAV, relative demand for and supply of such shares in the market, general market and economic conditions, and other factors beyond the control of the Fund, the Fund cannot assure you that Common Shares will trade at a price equal to or higher than NAV in the future. The Common Shares are designed primarily for long-term investors, and investors in the Common Shares should not view the Fund as a vehicle for trading purposes. See “Repurchase of Fund Shares; Conversion to Open-End Fund.”

Preferred Shares

As a fundamental policy, the Fund will not leverage its capital structure by issuing senior securities (as defined under the 1940 Act), such as preferred shares or debt instruments.

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RIGHTS OFFERINGS

The Fund may in the future, and at its discretion, choose to make offerings of Rights to its shareholders to purchase Common Shares. Rights may be issued independently or together with any other offered security and may or may not be transferable by the person purchasing or receiving the rights. In connection with a Rights offering to shareholders, the Fund would distribute certificates or other documentation evidencing the Rights and a prospectus supplement to the Fund’s shareholders as of the record date that the Fund sets for determining the shareholders eligible to receive Rights in such Rights offering. Any such future Rights offering will be made in accordance with the 1940 Act and, to the extent such Rights are transferable, will comply with applicable interpretations of the SEC or its staff, as such interpretations may be modified in the future, which currently require that: (i) the Fund’s Board of Trustees make a good faith determination that such offering would result in a net benefit to existing shareholders; (ii) the offering fully protects shareholders’ preemptive rights and does not discriminate among shareholders (except for the possible effect of not offering fractional rights); (iii) management uses its best efforts to ensure an adequate trading market in the Rights for use by shareholders who do not exercise such Rights; and (iv) the ratio of such transferable Rights offering does not exceed one new share for each three rights held.

The applicable prospectus supplement would describe the following terms of the Rights (to the extent each is applicable) in respect of which this Prospectus is being delivered:

A certain number of Rights would entitle the holder of the Right(s) to purchase for cash such number of shares at such exercise price as in each case is set forth in, or be determinable as set forth in, the prospectus supplement relating to the Rights offered thereby. Rights would be exercisable at any time up to the close of business on the expiration date for such Rights set forth in the prospectus supplement. After the close of business on the expiration date, all unexercised Rights would become void. Upon expiration of the Rights offering and the receipt of payment and the Rights certificate or other appropriate documentation properly executed and completed and duly executed at the corporate trust office of the Rights agent, or any other office indicated in the prospectus supplement, the Common Shares purchased as a result of such exercise will be issued as soon as practicable. To the extent permissible under applicable law, the Fund may determine to offer any unsubscribed offered securities directly to persons other than shareholders, to or through agents, underwriters or dealers or through a combination of such methods, as set forth in the applicable prospectus supplement.

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CERTAIN PROVISIONS IN THE DECLARATION OF TRUST AND BY-LAWS

General. The By-laws of the Fund provide that by becoming a shareholder of the Fund, each shareholder shall be deemed to have agreed to be bound by the terms of the Declaration of Trust and By-laws. However, neither the Declaration of Trust nor the By-laws purport to require the waiver of a shareholder’s rights under the federal securities laws.

Shareholder and Trustee Liability. Under Massachusetts law, shareholders could, under certain circumstances, be held personally liable for the Fund’s obligations. However, the Declaration of Trust contains an express disclaimer of shareholder liability for the Fund’s debts or obligations and requires that notice of such limited liability be given in each agreement, obligation or instrument entered into or executed by the Fund or the trustees. The Declaration of Trust further provides for indemnification out of the Fund’s assets and property for all loss and expense of any shareholder held personally liable for the Fund’s obligations. Thus, the risk of a shareholder incurring financial loss on account of shareholder liability is limited to circumstances in which the Fund would be unable to meet its obligations. The Fund believes that the likelihood of such circumstances is remote.

The Declaration of Trust provides that the Fund’s obligations are not binding upon the Fund’s trustees individually, but only upon the Fund’s assets and property, and that the trustees shall not be liable for errors of judgment or mistakes of fact or law. Nothing in the Declaration of Trust, however, protects a trustee against any liability to which the trustee would otherwise be subject by reason of willful misfeasance, bad faith, gross negligence or reckless disregard of the duties involved in the conduct of the trustee’s office.  

Anti-Takeover Provisions. The Declaration of Trust and By-laws include provisions that could limit the ability of other entities or persons to acquire control of the Fund or to convert the Fund to open-end status. The By-laws require the Board of Trustees be divided into three classes with staggered terms. See “Management of the Fund” in the SAI. This provision of the By-laws could delay for up to two years the replacement of a majority of the Board of Trustees. The Fund’s Declaration of Trust requires a vote by holders of at least two-thirds of the outstanding Common Shares, except as described below, to authorize (i) a conversion of the Fund from a closed-end to an open-end investment company, (ii) a merger or consolidation of the Fund with any corporation or a reorganization or recapitalization, (iii) a sale, lease or transfer of all or substantially all of the assets of the Fund (other than in the regular course of the Fund’s investment activities) prior to January 10, 2010, or (iv) a termination of the Fund prior to January 1, 2010, unless in any case such action has previously been approved, adopted or authorized by the affirmative vote of two-thirds of the total number of Trustees fixed in accordance with the Fund’s By-laws, in which case the affirmative vote of the holders of at least a majority of the Fund’s outstanding shares shall be required. None of the foregoing voting provisions may be amended or repealed except by the vote of at least two-thirds of the outstanding shares. The votes required to approve the conversion of the Fund from a closed-end to an open-end investment company are higher than those required by the 1940 Act. The Board of Trustees believes that the provisions of the Declaration of Trust relating to such higher votes are in the best interest of the Fund and its shareholders.

The provisions of the Fund’s Declaration of Trust and By-laws described above could have the effect of depriving the common shareholders of opportunities to sell their Common Shares at a premium over the then-current market price of the Common Shares by discouraging a third party from seeking to obtain control of the Fund in a tender offer or similar transaction. The overall effect of these provisions is to render more difficult the accomplishment of a merger or the assumption of control by a third party. However, they provide the advantage of potentially requiring persons seeking control of the Fund to negotiate with its management regarding the price to be paid and facilitating the continuity of the Fund’s investment objective and policies. The Fund’s Board of Trustees has considered the foregoing anti-takeover provisions and concluded that they are in the best interests of the Fund.

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Procedural Requirements on Derivative Actions, Exclusive Jurisdiction and Jury Trial Waiver. The By-laws of the Fund contain certain provisions affecting potential shareholder claims against the Fund, including procedural requirements for derivative actions, an exclusive forum provision, and the waiver of shareholder rights to a jury trial. Massachusetts is considered a “universal demand” state, meaning that under Massachusetts corporate law a shareholder must make a demand on the company before bringing a derivative action (i.e., a lawsuit brought by a shareholder on behalf of the company). The By-laws of the Fund provide detailed procedures for the bringing of derivative actions by shareholders which are modeled on the substantive provisions of the Massachusetts corporate law derivative demand statute. The procedures are intended to permit legitimate inquiries and claims while avoiding the time, expense, distraction, and other harm that can be caused to the Fund or its shareholders as a result of spurious shareholder demands and derivative actions. Among other things, these procedures:

These procedures may be more restrictive than procedures for bringing derivative suits applicable to other investment companies.

The By-laws also require that actions by shareholders against the Fund, except for actions under the U.S. federal securities laws, be brought only in a certain federal court in Massachusetts, or if not permitted to be brought in federal court, then in the Business Litigation Session of the Massachusetts Superior Court in Suffolk County (the “Exclusive Jurisdictions”), and that the right to jury trial be waived to the fullest extent permitted by law. Other investment companies may not be subject to similar restrictions. The designation of Exclusive Jurisdictions may make it more expensive for a shareholder to bring a suit than if the shareholder were permitted to select another jurisdiction. In the event a shareholder selects another jurisdiction to bring its suit and the venue for such suit is subsequently changed back to an Exclusive Jurisdiction through the legal process, then such shareholder shall be required to reimburse all expenses incurred by the Fund or any other person in effecting such change of venue back to the Exclusive Jurisdiction. Also, the designation of Exclusive Jurisdictions and the waiver of jury trials limit a shareholder’s ability to litigate a claim in the jurisdiction and in a manner that may be more favorable to the shareholder. It is possible that a court may choose not to enforce these provisions of the Fund’s By-laws.

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Preemptive Rights. The Declaration of Trust provides that Common Shareholders shall have no right to acquire, purchase or subscribe for any shares or investments of the Fund, other than such right, if any, as the Fund’s Board of Trustees in its discretion may determine. As of the date of this Prospectus, no preemptive rights have been granted by the Board of Trustees.

Reference should be made to the Declaration of Trust and By-laws on file with the SEC for the full text of these provisions.

REPURCHASE OF FUND SHARES; CONVERSION TO OPEN-END FUND

The Fund is a closed-end investment company and as such its shareholders will not have the right to cause the Fund to redeem their shares. Instead, the Common Shares will trade in the open market at a price that will be a function of several factors, including dividend levels (which are in turn affected by expenses), NAV, call protection, dividend stability, portfolio credit quality, relative demand for and supply of such shares in the market, general market and economic conditions and other factors. Because shares of closed-end investment companies may frequently trade at prices lower than NAV, the Fund’s Board of Trustees has currently determined that, at least annually, it will consider action that might be taken to reduce or eliminate any material discount from NAV in respect of Common Shares, which may include the repurchase of such shares in the open market or in private transactions, the making of a tender offer for such shares at NAV, or the conversion of the Fund to an open-end investment company. The Fund cannot assure you that its Board of Trustees will decide to take any of these actions, or that share repurchases or tender offers will actually reduce market discount.

If the Fund converted to an open-end investment company, the Common Shares would no longer be listed on the NYSE or elsewhere and it would likely have to significantly reduce any leverage it is then employing, which may require a repositioning of its investment portfolio, which may in turn generate substantial transaction costs, which would be borne by Common Shareholders, and may adversely affect Fund performance and Fund distributions. In contrast to a closed-end investment company, shareholders of an open-end investment company may require the company to redeem their shares at any time (except in certain circumstances as authorized by the 1940 Act or the rules thereunder) at their NAV, less any redemption charge that is in effect at the time of redemption. The Fund currently expects that any such redemptions would be made in cash. The Fund may charge sales or redemption fees upon conversion to an open-end fund. In order to avoid maintaining large cash positions or liquidating favorable investments to meet redemptions, open-end investment companies typically engage in a continuous offering of their shares. Open-end investment companies are thus subject to periodic asset in-flows and out-flows that can complicate portfolio management. The Board of Trustees may at any time propose conversion of the Fund to an open-end investment company depending upon its judgment as to the advisability of such action in light of circumstances then prevailing.

Before deciding whether to take any action if the Common Shares trade below NAV, the Fund’s Board of Trustees would consider all relevant factors, including the extent and duration of the discount, the liquidity of the Fund’s portfolio, the impact of any action that might be taken on the Fund or its shareholders, and market considerations. Based on these considerations, even if the Fund’s shares should trade at a discount, the Board of Trustees may determine that, in the interest of the Fund and its shareholders, no action should be taken.

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TAX MATTERS

The following information is meant as a general summary for U.S. Common Shareholders. Please see the SAI for additional information. This summary does not discuss the tax consequences of an investment in Rights. The tax consequences of such an investment will be discussed in the relevant prospectus supplement. Investors should rely on their own tax adviser for advice about the particular federal, state and local tax consequences to them of investing in the Fund.

The Fund has elected and intends to qualify each year to be treated as a RIC under Subchapter M of the Code. In order to qualify for treatment as a RIC, the Fund must satisfy certain requirements regarding the sources of its income, the diversification of its assets and the distribution of its income. As a RIC, the Fund is not expected to be subject to U.S. federal income tax. The Fund primarily invests in municipal securities issued by states, cities and local authorities and certain possessions and territories of the United States (such as Puerto Rico or Guam) or municipal securities whose income is otherwise exempt from U.S. federal income tax and federal alternative minimum tax applicable to individuals. To qualify to pay exempt-interest dividends, which are treated as items of interest excludable from gross income for U.S. federal income tax purposes, at least 50% of the value of the total assets of the Fund must consist of obligations exempt from regular income tax as of the close of each quarter of the Fund’s taxable year. If the proportion of taxable investments held by the Fund exceeds 50% of the Fund’s total assets as of the close of any quarter of any Fund taxable year, the Fund would not for that taxable year satisfy the general eligibility test that would otherwise permit it to pay exempt-interest dividends. A shareholder treats an exempt-interest dividend as interest on state and local bonds exempt from regular federal income tax. Federal income tax law imposes an alternative minimum tax. Interest on certain municipal securities, such as certain private activity bonds, is included as an item of tax preference in determining the amount of a taxpayer’s alternative minimum taxable income. To the extent that the Fund receives income from such municipal securities, a portion of the dividends paid by the Fund, although exempt from regular federal income tax, will be taxable to shareholders whose tax liabilities are determined under the federal alternative minimum tax. The Fund will annually provide a report indicating the percentage of the Fund’s income attributable to municipal securities and the percentage includable in federal alternative minimum taxable income.

In addition to exempt-interest dividends, the Fund may also distribute to its shareholders amounts that are treated as long-term capital gain or ordinary income (which may include short-term capital gains). These distributions are generally subject to regular federal income tax, whether or not reinvested in additional shares. Net capital gain distributions (the excess of net long-term capital gain over net short-term capital loss) that are properly reported to Fund shareholders as capital dividends are generally taxable at rates applicable to long-term capital gains regardless of how long a shareholder has held its shares. Long-term capital gains are currently taxable to non-corporate shareholders at rates of up to 20%. Distributions of net short-term capital gains for a taxable year in excess of net long-term capital losses for such taxable year generally will be taxable at ordinary income rates to a shareholder receiving such distributions. The Fund does not expect that any part of its distributions to shareholders from its investments will qualify for the dividends-received deduction available to corporate shareholders or as “qualified dividend income,” which is taxable to non-corporate shareholders at preferential U.S. federal income tax rates.

A 3.8% net investment income tax generally applies to all or a portion of the net investment income of a shareholder who is an individual and not a nonresident alien for U.S. federal income tax purposes and who has adjusted gross income (subject to certain adjustments) that exceeds a threshold amount ($250,000 if married filing jointly or if considered a “surviving spouse” for federal income tax purposes, $125,000 if married filing separately, and $200,000 in other cases). This 3.8% tax also applies to all or a portion of the undistributed net investment income of certain shareholders that are estates and trusts. For these purposes, interest, dividends, and certain capital gains are generally taken into account in computing a shareholder’s net investment income, but exempt-interest dividends are not taken into account.

As a RIC, the Fund will not be subject to federal income tax in any taxable year provided that it meets certain requirements. As described in “Distributions” above, the Fund may retain for investment some (or all) of its net capital gain. If the Fund retains any net capital gain or taxable net investment income, it will be subject to tax at the regular corporate rate on the amount retained. If the Fund retains any net capital gain, it may designate the retained amount as undistributed capital gains in a notice to its shareholders who, if subject to federal income tax on long-term capital gains, (i) will be required to include in income for federal income tax purposes, as long-term capital gain, their share of such undistributed amount; (ii) will be deemed to have paid their proportionate shares of the tax paid by the Fund on such undistributed amount and will be entitled to credit that amount of tax against their federal income tax liabilities, if any; and (iii) will be entitled to claim refunds to the extent the credit exceeds such liabilities. For federal income tax purposes, the tax basis of shares owned by a shareholder of the Fund will be increased by an amount equal to the difference between the amount of undistributed capital gains included in the shareholder’s gross income and the tax deemed paid by the shareholder.

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Dividends declared by the Fund in October, November or December, payable to shareholders of record in such a month, and paid during the following January will be treated as having been received by shareholders in the year the distributions were declared.

Each shareholder will receive an annual statement summarizing the U.S. federal income tax status of all distributions.

The repurchase, sale or exchange of Common Shares normally will result in capital gain or loss to holders of Common Shares who hold their shares as capital assets. Generally, a shareholder’s gain or loss will be long-term capital gain or loss if the shares have been held for more than one year even though the increase in value in such Common Shares may be at least partly attributable to tax-exempt interest income. Present law taxes both long-term and short-term capital gains of corporations at the rates applicable to ordinary income. For non-corporate taxpayers, however, long-term capital gains are currently taxed at rates of up to 20%. Short-term capital gains and other ordinary income are taxed to non-corporate taxpayers at ordinary income rates. If a shareholder sells or otherwise disposes of Common Shares before holding them for six months, any loss on the sale or disposition will be treated as a long-term capital loss to the extent of any amounts treated as distributions to the Common Shareholder of long-term capital gain (including any amount credited to the shareholder as undistributed capital gain) or (2) disallowed to the extent of exempt-interest dividends received by a Common Shareholder. Any loss realized by a shareholder on the disposition of shares held 6 months or less is disallowed to the extent of the amount of exempt-interest dividends received by the shareholder with respect to Common Shares. Any loss realized on a sale or exchange of shares of the Fund will be disallowed to the extent those shares of the Fund are replaced by substantially identical shares of the Fund (including shares acquired by reason of participation in the Plan) within a period of 61 days beginning 30 days before and ending 30 days after the date of disposition of the original shares, or to the extent the shareholder enters into a contract or option to repurchase shares within such period. In that event, the basis of the replacement shares of the Fund will be adjusted to reflect the disallowed loss.

Any interest on indebtedness incurred or continued to purchase or carry the Fund’s shares to which exempt-interest dividends are allocated is not deductible. Under certain applicable rules, the purchase or ownership of shares may be considered to have been made with borrowed funds even though such funds are not directly used for the purchase or ownership of the shares. In addition, if you receive social security or certain railroad retirement benefits, you may be subject to U.S. federal income tax on a portion of such benefits as a result of receiving investment income, including exempt-interest dividends and other distributions paid by the Fund.

The Fund may be required to withhold (as “backup withholding”) U.S. federal income tax from distributions (including exempt-interest dividends) and repurchase proceeds payable to a shareholder if the shareholder fails to provide the Fund with his or her correct taxpayer identification number or to make required certifications, or if the shareholder has been notified by the IRS that he or she is subject to backup withholding. The backup withholding rate is 24%. Backup withholding is not an additional tax; rather, it is a way in which the IRS ensures it will collect taxes otherwise due. Any amounts withheld may be credited against a shareholder’s U.S. federal income tax liability.

The Fund may invest in municipal securities that pay interest that is taxable under the federal alternative minimum tax. If you are, or as a result of investment in the Fund would become, subject to the federal alternative minimum tax, the Fund may not be a suitable investment for you. In addition, distributions of taxable ordinary income (including any net short-term capital gain) will be taxable to shareholders as ordinary income (and not eligible for favorable taxation as “qualified dividend income”), and capital gain dividends will be taxable as long-term capital gains.

Other State and Local Tax Matters. The exemption from U.S. federal income tax for exempt-interest dividends generally does not result in exemption for such dividends under the income or other tax laws of any state or local taxing authority. In some states, however, the portion of any exempt-interest dividends derived from interest received by the Fund on its holdings of that state’s securities and those of its political subdivisions and instrumentalities is exempt from the state’s income tax. The Fund will report annually to its shareholders the percentage of interest income earned by the Fund during the preceding year on tax-exempt obligations indicating, on a state-by-state basis, the source of such income. Shareholders of the Fund are advised to consult their own tax advisors about the tax laws of their state and locality of residence. Please refer to the SAI for more detailed information.

CUSTODIAN AND TRANSFER AGENT

The custodian of the assets of the Fund is State Street Bank and Trust Company, located at One Congress Street, Suite 1, Boston, MA 02114-2016 (the “Custodian”). The Custodian performs custodial, fund accounting and portfolio accounting services. The Fund’s transfer, shareholder services and dividend paying agent with respect to the Fund’s Common Shares is Computershare Inc. and Computershare Trust Company, N.A., located at 150 Royall Street, Canton, MA 02021. The transfer agent, tender and dividend paying agent will be identified in the applicable prospectus supplement.

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INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

PricewaterhouseCoopers LLP (“PwC”) an independent registered public accounting firm, provides auditing services to the Fund. The principal business address of PwC is One North Wacker Drive, Chicago, IL 60606.

LEGAL MATTERS

Certain legal matters in connection with the offering will be passed upon for the Fund by Stradley Ronon Stevens & Young, LLP, located at 2005 Market Street, Suite 2600, Philadelphia, PA 19103. Stradley Ronon Stevens & Young, LLP may rely as to certain matters of Massachusetts law on the opinion of Morgan, Lewis & Bockius LLP. Any additional legal opinions will be described in a prospectus supplement.

AVAILABLE INFORMATION

The Fund is subject to the informational requirements of the Securities Exchange Act of 1934, as amended (the “Exchange Act”) and the 1940 Act and is required to file reports, proxy statements and other information with the SEC. Reports, proxy statements, and other information about the Fund can be inspected at the offices of the NYSE.

This Prospectus does not contain all of the information in the Fund’s Registration Statement, including amendments, exhibits, and schedules. Statements in this Prospectus about the contents of any contract or other document are not necessarily complete and, in each instance, reference is made to the copy of the contract or other document filed as an exhibit to the Registration Statement, each such statement being qualified in all respects by this reference.

Additional information about the Fund and the Securities can be found in the Fund’s Registration Statement (including amendments, exhibits, and schedules) on Form N-2 filed with the SEC. The SEC maintains a website (http://www.sec.gov) that contains the Fund’s Registration Statement, other documents incorporated by reference, and other information the Fund has filed electronically with the SEC, including proxy statements and reports filed under the Exchange Act.

INCORPORATION BY REFERENCE

The documents listed below, and any reports and other documents subsequently filed with the SEC pursuant to Section 30(b)(2) of the 1940 Act and Sections 13(a), 13(c), 14 or 15(d) of the Exchange Act prior to the termination of the offering will be incorporated by reference into this Prospectus and deemed to be part of this Prospectus from the date of the filing of such reports and documents:

The information incorporated by reference is considered to be part of this Prospectus, and later information that the Fund files with the SEC will automatically update and supersede this information. Incorporated materials not delivered with the Prospectus may be obtained, without charge, by calling (800) 257-8787, by writing to the Fund at 333 West Wacker Drive, Chicago, Illinois 60606, or from the Fund’s website (http://www.nuveen.com).