HIGHLAND INCOME FUND

(the “Fund”)

Supplement dated March 10, 2023 to the Fund’s Statement of Additional Information (the “SAI”), dated June 26, 2019, as supplemented from time to time

This supplement provides new and additional information beyond that contained in the SAI and should be read in conjunction with the SAI. Capitalized terms and certain other terms used in this supplement, unless otherwise defined in this supplement, have the meanings assigned to them in the SAI.

Effective February 13, 2023, the following will replace the “Management of the Trust” including the headings “Trustees”, “Information about Each Trustee’s Experience, Qualifications, Attributes, or Skills for Board Membership”, “Role of the Board of Trustees, Leadership Structure and Risk Oversight”, “ Compensation of Trustees” and “Share Ownership” beginning on page 26 of the SAI:

MANAGEMENT OF THE TRUST

Trustees

The Board provides broad oversight over the operations and affairs of the Trust and protects the interests of shareholders. The Board has overall responsibility to manage and control the business affairs of the Trust, including the complete and exclusive authority to establish policies regarding the management, conduct and operation of the Trust’s business. The names and birthdates of the Trustees and officers of the Trust, the year each was first elected or appointed to office, their principal business occupations during the last five years, the number of funds overseen by each Trustee and other directorships or trusteeships they hold are shown below. The business address of the Trust, the Adviser and their Board members and officers is 300 Crescent Court, Suite 700, Dallas, Texas 75201, unless otherwise specified below.

Information About Each Trustee’s Experience, Qualifications, Attributes, or Skills for Board Membership

The following provides an overview of the considerations that led the Board to conclude that each individual serving as a Trustee of the Trust should so serve, as well as each Trustee’s name and certain biographical information as reported by them to the Trust. Among the factors the Board considered when concluding that an individual should serve on the Board were the following: (i) the individual’s business and professional experience and accomplishments; (ii) the individual’s ability to work effectively with the other members of the Board; (iii) the individual’s prior experience, if any, serving on company boards (including public companies and, where relevant, other investment companies) and the boards of other complex enterprises and organizations; and (iv) how the individual’s skills, experiences and attributes would contribute to an appropriate mix of relevant skills and experience on the Board.

In respect of each Trustee, the individual’s professional accomplishments and prior experience, including, in some cases, in fields related to the operations of the Trust, were a significant factor in the determination that the individual should serve as a Trustee of the Trust. Each Trustee’s professional experience and additional considerations that contributed to the Board’s conclusion that an individual should serve on the Board are summarized in the table below.

The “NexPoint Fund Complex,” as referred to herein consists of: each series of NexPoint Funds I (“NFI”), each series of NexPoint Funds II (“NFII”), Highland Global Allocation Fund (“GAF”), Highland Income Fund (“HFRO”), NexPoint Real Estate Strategies Fund (“NRESF”), and NexPoint Capital, Inc. (the “BDC”), a closed-end management investment company that has elected to be treated as a business development company under the 1940 Act.

OFFICERS

Role of the Board of Trustees, Leadership Structure and Risk Oversight

The Role of the Board

The Board oversees the management and operations of the Fund. Like most registered investment companies, the day-to-day management and operation of the Fund is performed by various service providers to the Fund, such as the Adviser, and the distributor, administrator, custodian, and transfer agent. The Board has appointed senior employees of certain of these service providers as officers of the Fund, with responsibility to monitor and report to the Board on the Fund’s operations. The Board receives regular reports from these officers and service providers regarding the Fund’s operations. For example, the Treasurer provides reports as to financial reporting matters and investment personnel report on the performance of the Fund. The Board has appointed a Chief Compliance Officer who administers the Fund’s compliance program and regularly reports to the Board as to compliance matters. Some of these reports are provided as part of formal Board meetings, which are typically held quarterly, and involve the Board’s review of, among other items, recent Fund operations. The Board also periodically holds telephonic meetings as part of its review of the Fund’s activities. From time to time one or more members of the Board may also meet with management in less formal settings, between scheduled Board meetings, to discuss various topics. In all cases, however, the role of the Board and of any individual Trustee is one of oversight and not of management of the day-to-day affairs of the Fund and its oversight role does not make the Board a guarantor of the Fund’s investments, operations or activities.

Board Structure and Leadership

The Board has structured itself in a manner that it believes allows it to perform its oversight function effectively. The Board consists of five Trustees, four of whom are not “interested persons,” as defined in the 1940 Act and are “independent” as defined in Rule 303A.02 of the New York Stock Exchange Listed Company Manual. The remaining Trustee, Mr. Honis, is currently treated as an “interested person” of the Fund (an “Interested Trustee”). Mr. Powell serves as Chairman of the Board. The Trustees meet periodically throughout the year to oversee the Fund’s activities, review contractual arrangements with service providers for the Fund and review the Fund’s performance. Effective April 11, 2019, the Fund changed its fiscal year end to December 31. The previous fiscal year end was June 30. During the fiscal year ended December 31, 2022, the Board convened nine times. Each Trustee attended at least 75% of the aggregate of the total number of meetings of the Board and Committees on which he or she served during the periods that he or she served. The Fund encourages, but does not require, Trustees to attend the Annual Meeting.

The Board periodically reviews its leadership structure, including the role of the Chairman. The Board also completes an annual self-assessment during which it reviews its leadership and Committee structure and considers whether its structure remains appropriate in light of the Fund’s current operations. The Board believes that its leadership structure, including the current percentage of the Board who are Independent Trustees is appropriate given its specific characteristics. These characteristics include: (i) the extent to which the work of the Board is conducted through the standing committees, and that the Audit and Qualified Legal Compliance Committee (the “Audit Committee”) and the Governance and Compliance Committee meetings are each chaired by an Independent Trustee; (ii) the extent to which the Independent Trustees meet as needed, together with their independent legal counsel, in the absence of members of management and any member of the Board who is considered an “interested person” of the Fund; and (iii) Mr. Powell’s and Mr. Honis’ previous positions with the Adviser and historical affiliates of the Adviser, which enhances the Board’s understanding of the operations of the Adviser.

Board Oversight of Risk Management. The Board’s role is one of oversight, rather than active management. This oversight extends to the Fund’s risk management processes. These processes are embedded in the responsibilities of officers of, and service providers to, the Fund. For example, the Adviser and other service providers to the Fund are primarily responsible for the management of the Fund’s investment risks. The Board has not established a formal risk oversight committee; however, much of the regular work of the Board and its standing Committees addresses aspects of risk oversight. For example, the Trustees seek to understand the key risks facing the Fund, including those involving conflicts of interest; how management identifies and monitors these risks on an ongoing basis; how management develops and implements controls to mitigate these risks; and how management tests the effectiveness of those controls.

In the course of providing that oversight, the Board receives a wide range of reports on the Fund’s activities from the Adviser and other service providers, including reports regarding the Fund’s investment portfolio, the compliance of the Fund with applicable laws, and the Fund’s financial accounting and reporting. The Board also meets periodically with the Fund’s Chief Compliance Officer to receive reports regarding the compliance of the Fund with the federal securities laws and the Fund’s internal compliance policies and procedures and meets with the Fund’s Chief Compliance Officer periodically, including at least annually, to review the Chief Compliance Officer’s annual report, including the Chief Compliance Officer’s risk-based analysis for the Fund. The Board’s Audit Committee also meets regularly with the Treasurer and the Fund’s independent registered public accounting firm to discuss, among other things, the internal control structure of the Fund’s financial reporting function. The Board also meets periodically with the portfolio managers of the Fund to receive reports regarding the management of the Fund, including its investment risks.

The Board recognizes that not all risks that may affect the Fund can be identified, that it may not be practical or cost-effective to eliminate or mitigate certain risks, that it may be necessary to bear certain risks (such as investment-related risks) to achieve the Fund’s goals, that reports received by the Trustees with respect to risk management matters are typically summaries of the relevant information, and that the processes, procedures and controls employed to address risks may be limited in their effectiveness. As a result of the foregoing and other factors, risk management oversight by the Board and by the Committees is subject to substantial limitations.

Committees of the Board

The Board conducts much of its work through certain standing Committees. The Board has three Committees, the Audit Committee, the Governance and Compliance Committee, and the Distribution and Alternatives Oversight Committee, each of which are discussed in greater detail below. The Board has adopted charters for each of these committees.

The Audit and Qualified Legal Compliance Committee. The members of the Audit Committee are Dr. Froehlich, Messrs. Ward and Powell and Ms. McWhorter, each of whom is independent for purposes of the 1940 Act. The Audit Committee is responsible for (i) approving the Fund’s independent accountants, (ii) reviewing with the Fund’s independent accountants the plans and results of the audit engagement and the adequacy of the Fund’s internal accounting controls and (iii) approving professional services provided by the Fund’s independent accountants. The Audit Committee is charged with compliance with Rules 205.2(k) and 205.3(c) of Title 17 of the Code of Federal Regulations regarding alternative reporting procedures for attorneys representing the Fund who appear and practice before the SEC on behalf of the Fund. The Audit Committee is also responsible for reviewing and overseeing the valuation of debt and equity securities that are not publicly traded or for which current market values are not readily available pursuant to policies and procedures adopted by the Board. The Board and Audit Committee will use the services of one or more independent valuation firms to help them determine the fair value of these securities. In addition, each member of the Audit Committee meets the current independence and experience requirements of Rule 10A-3 under the Securities Exchange Act of 1934, as amended (the “1934 Act”). The Audit Committee met five times during the fiscal year ended December 31, 2022. Mr. Ward acts as the Chairman of the Audit Committee and as the audit committee financial expert.

The Governance and Compliance Committee. The Fund’s Governance and Compliance Committee’s function is to oversee and make recommendations to the full Board or the Independent Trustees, as applicable, with respect to the governance of the Fund, selection and nomination of Trustees, compensation of Trustees, and related matters, as well as to oversee and assist Board oversight of the Fund’s compliance with legal and regulatory requirements and to seek to address any potential conflicts of interest between the Fund and NexPoint in connection with any potential or existing litigation or other legal proceeding related to securities held by the Fund and the Adviser or another client of the Adviser. The Governance and Compliance Committee is also responsible for at least annually evaluating each Trustee and determining whether to recommend each Trustee’s continued service in that capacity. The Governance and Compliance Committee will consider recommendations for Trustee nominees from shareholders sent to the Secretary of the Fund, 300 Crescent Court, Suite 700, Dallas, Texas 75201. A nomination submission must include all information relating to the recommended nominee that is required to be disclosed in solicitations or proxy statements for the election of Trustees, as well as information sufficient to evaluate the recommended nominee’s ability to meet the responsibilities of a Trustee of the Fund. Nomination submissions must be accompanied by a written consent of the individual to stand for election if nominated by the Board and to serve if elected by the shareholders, and such additional information must be provided regarding the recommended nominee as reasonably requested by the Governance and Compliance Committee. The Governance and Compliance Committee is currently comprised of Dr. Froehlich, Messrs. Ward and Powell and Ms. McWhorter, each of whom is independent for purposes of the 1940 Act. Dr. Froehlich serves as the Chairman of the Governance and Compliance Committee. The Governance and Compliance Committee met five times during the fiscal year ended December 31, 2022.

The Distribution and Alternatives Oversight Committee. The members of the Distribution and Alternatives Oversight Committee are Dr. Froehlich, Messrs. Honis, Ward and Powell and Ms. McWhorter. The Distribution and Alternatives Oversight Committee is responsible for reviewing arrangements with financial intermediaries who provide service to the Fund, including Fund payments to financial intermediaries, and for overseeing any funds that, in the Board’s determination, employ alternative investment strategies. Mr. Honis serves as Chairman of the Distribution and Alternatives Oversight Committee. The Distribution and Alternatives Oversight Committee met four times during the fiscal year ended December 31, 2022.

Compensation of Trustees

The executive officers of the Fund receive no direct remuneration from the Fund. Each Trustee who oversees all of the funds in the Fund Complex receives an annual retainer of $150,000 payable in quarterly installments and allocated among each portfolio in the Fund Complex based upon relative net assets. The Trustees are reimbursed for actual out-of-pocket expenses relating to attendance at meetings. The Trustees do not receive any separate compensation in connection with service on Committees or for attending Board or Committee Meetings; however, the Chairman of the Board and the Chairman of the Audit Committee each receive an additional payment of $10,000 payable in quarterly installments and allocated among each portfolio in the Fund Complex based on relative net assets. The Trustees do not have any pension or retirement plan.

The following table summarizes the compensation paid by the Fund to its Trustees and the aggregate compensation paid by the Fund Complex to the Trustees for services rendered in the fiscal year ended December 31, 2022.

Share Ownership

Set forth in the table below is the dollar range of shares of the Trust and the aggregate dollar range of shares beneficially owned by each Trustee of the Trust as of December 31, 2022.

PLEASE RETAIN THIS SUPPLEMENT FOR FUTURE REFERENCE.

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