Filed pursuant to Rule 424(b)(3)

Registration No. 333-281687

BLACKSTONE PRIVATE MULTI-ASSET CREDIT AND INCOME FUND
Supplement No. 1 dated October 15, 2025
to the Prospectus dated March 10, 2025

This prospectus supplement (“Supplement”) is part of and should be read in conjunction with the prospectus of Blackstone Private Multi-Asset Credit and Income Fund (“we,” “our” or the “Fund”), dated March 10, 2025 (the “Prospectus”). Unless otherwise defined herein, capitalized terms used in this Supplement shall have the same meanings as in the Prospectus.

Appointment of New Chief Executive Officer, Interested Trustee and Chair of the Board of Trustees, Co-Chief Investment Officer and Head of Stakeholder Relations

On October 14, 2025, the Board of Trustees approved the following changes effective November 1, 2025:

The last sentence under “Management” on page 107 of the Prospectus is deleted and replaced with the following:

Mr. Oneglia, experience as an executive, investment professional and Blackstone business leader; Ms. Collins, experience as an executive and service as a board member of another registered management investment company; Ms. Fuller, experience as an executive and service as a board member of other registered management investment companies; Mr. Clark, experience as an investment professional; and Ms. Pascucci, experience as an investment professional.

The “Interested Trustee” section of the table under “Trustees” on page 107 of the Prospectus is replaced with the following:

The table under “Executive Officers Who are Not Trustees” on page 108 of the Prospectus is amended to include the following information and to remove Dan Oneglia:

The following paragraph is moved from the “Executive Officers Who Are Not Trustees” subsection under “Biographical Information” to replace the information in the “Interested Trustees” subsection under “Biographical Information” on page 108 of the Prospectus:

Dan Oneglia, Senior Managing Director, Co-CIO of BMACX, Global CIO of Liquid Credit Strategies. Mr. Oneglia is a Senior Managing Director and the Global CIO of Liquid Credit Strategies. He also leads liquid asset allocation for BXCI based in New York. Before joining Blackstone, in 2019, he spent 20 years at Goldman Sachs where he was a partner and led the Americas Multi-Strategy Investment (MSI) team within the Special Situations Group (SSG). Mr. Oneglia graduated from Princeton University with a B.A. in History and a Certificate in Latin American Studies. Mr. Oneglia serves as the Chair of the Board of Trustees for The New York Foundling.

The “Executive Officers Who Are Not Trustees” subsection under “Biographical Information” beginning on page 109 of the Prospectus is amended to include the following information:

Eugene Lee, Managing Director, Co-CIO of BMACX. Mr. Lee is a Managing Director in BXCI based in New York, where he leads portfolio management and asset allocation for BXCI’s multi-asset credit strategies. Before joining Blackstone, Mr. Lee worked at Goldman Sachs within the Special Situations Group as a member of the Multi-Strategy and Alternative Energy Investing teams. In this capacity, Mr. Lee invested across a broad range of asset classes and industries throughout North and South America. Mr. Lee received an AB/SM in Economics and Applied Mathematics from Harvard University and studied violin performance at the New England Conservatory. Mr. Lee serves on the board of directors of the Harvard-Radcliffe Orchestra Foundation.

Stacy Wang, Managing Director, Head of Stakeholder Relations. Ms. Wang is a Managing Director and the Head of Stakeholder Relations for Blackstone Private Credit Fund (BCRED) and Blackstone Secured Lending Fund (BXSL) for Blackstone Credit and Insurance (BXCI) based in New York. Prior to her current role, Ms. Wang focused on fundraising, product strategy, and client relationships across private and opportunistic credit products for institutional and retail investors. Prior to joining Blackstone in 2015, Ms. Wang worked as an Investment Banking Associate at Natixis, where she focused on leveraged finance and M&A transactions. Ms. Wang graduated from the Stern School of Business at New York University with a BS in Finance and Journalism.

The second sentence of the second paragraph under “Board Leadership Structure” on page 113 of the Prospectus is deleted and replaced with the following:

The Board of Trustees has appointed Dan Oneglia to serve in the role of chairperson of the Board of Trustees.

The “Interested Trustees” section of the table under “Dollar Range of Equity Securities Owned by Trustees” on page 114 of the Prospectus is replaced with the following:

The biography for Eugene Lee is deleted from the section “Members of the Investment Committee and Portfolio Managers Who Are Not Our Trustees or Executive Officers” on page 121 of the Prospectus.

The table under “Control Persons and Principal Shareholders” on page 180 of the Prospectus is amended to include the following information:

Capitalized terms not defined herein have the meanings assigned to them in the Prospectus.

Please retain this supplement for future reference.