BSL Blackstone Senior Floating Rate 2027 Term Fund

Filed pursuant to Rule 424(b)(3)

Registration No. 333-261457

BLACKSTONE SENIOR FLOATING RATE 2027 TERM FUND

Supplement No. 5, dated January 4, 2024, to the Prospectus (the “Prospectus”) and the Statement of Additional Information (the “SAI”) dated January 26, 2022, for Common Shares of Beneficial Interest

Appointment of New Trustee, Chairman, President and Chief Executive Officer

On December 18, 2023, the Board of Trustees elected Robert Zable to serve as Trustee, Chairman, President and Chief Executive Officer of the Fund, effective January 1, 2024. Robert Zable is a Senior Managing Director and the Global Head of Blackstone Credit’s Liquid Credit Strategies group (“LCS”). Prior to being appointed Global Head, Mr. Zable was Senior Portfolio Manager in charge of LCS’ U.S. CLO portfolios. Mr. Zable sits on the Global Syndicated Credit, US Syndicated Credit, Global Structured Credit and CLO Origination Investment Committees. Prior to joining Blackstone Credit, then known as GSO Capital Partners, in 2007 Mr. Zable was a Vice President at FriedbergMilstein LLC, where he was responsible for credit opportunity investments and junior capital origination and execution. Mr. Zable began his career at JP Morgan Securities Inc., where he focused on leveraged finance in New York and London. Mr. Zable received a BS from Cornell University and an M.B.A in Finance from The Wharton School at the University of Pennsylvania. Mr. Zable was also elected to serve as Trustee, Chairman, President and Chief Executive Officer of Blackstone Floating Rate Enhanced Income Fund, Blackstone Long-Short Credit Income Fund, and Blackstone Strategic Credit 2027 Term Fund.

Mr. Zable replaces Daniel H. Smith as Trustee, Chairman, President and Chief Executive Officer of the Fund.

Appointment of New Executive Vice President and Assistant Secretary

On December 18, 2023, the Board of Trustees elected Robert Post to serve as Executive Vice President and Assistant Secretary, effective January 1, 2024. Mr. Post is a Principal and Portfolio Manager of the US leveraged loan and high yield strategies in Blackstone Credit’s LCS unit. Prior to joining Blackstone Credit in 2017, Mr. Post was a Junior Portfolio Manager at BlackRock, where his responsibilities included various leveraged loan and high yield mandates. Previously, Mr. Post was an Analyst at BMO Capital Markets, where he was involved with the ongoing monitoring and structuring of leveraged finance transactions. Mr. Post began his career at MetLife Investments as a credit analyst focused on corporate bonds. Mr. Post received a B.A. in Economics with a concentration in Financial Markets from Colby College. Mr. Post was also elected to serve as Executive Vice President and Assistant Secretary of Blackstone Floating Rate Enhanced Income Fund, Blackstone Long-Short Credit Income Fund, and Blackstone Strategic Credit 2027 Term Fund.

Mr. Post replaces Robert Zable as Executive Vice President and Assistant Secretary of the Fund.

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The following information replaces the information under “Interested Trustee” in the table under “Board of Trustees” on page 14 of the SAI:

2

The following clause replaces the clause beginning after the second semi-colon in the first sentence under “Experience of Trustees” on page 14 of the SAI:

; as to each Trustee other than Mr. Zable, his status as not being an “interested person” as defined in the 1940 Act; and, as to Mr. Zable, his role with Blackstone Credit and Blackstone Inc.

The following clause replaces the description of Mr. Smith’s experience in the third sentence under “Experience of Trustees” on page 15 of the SAI:

; and Mr. Zable, experience as an executive and portfolio manager and leadership roles with Blackstone Credit’s Liquid Credit Strategies group.

The following information replaces the information under “Interested Trustees” in the table under “Share Ownership” on page 15 of the SAI:

The following information replaces the information under “Interested Trustees” in the table under “Compensation of Trustees” on page 16 of the SAI:

The following information replaces the information in the row where Mr. Smith’s name appears in the table under “Officers of the Fund” on page 18 of the SAI:

3

The following information replaces the information in the row where Mr. Zable’s name appears in the table under “Officers of the Fund” on page 18 of the SAI:

Capitalized terms not defined herein have the meanings assigned to them in the Prospectus or SAI, as applicable.

Please retain this supplement for future reference.

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