BlackRock Floating Rate Income Trust : BGT)

PROSPECTUS SUPPLEMENT

(To Prospectus dated December 28, 2022)

BLACKROCK FLOATING RATE INCOME TRUST

Up to 11,000,000 Common Shares of Beneficial Interest

BlackRock Floating Rate Income Trust (the "Trust," "we," "us" or "our") is offering for sale up to 11,000,000 of our common shares of beneficial interest ("common shares"). Our common shares are listed on the New York Stock Exchange ("NYSE") under the symbol "BGT." As of the close of business on January 6, 2023, the last reported net asset value per share of our common shares was $12.55 and the last reported sales price per share of our common shares on the NYSE was $11.18.

The Trust is a diversified, closed-end management investment company registered under the Investment Company Act of 1940, as amended (the "Investment Company Act"). The Trust's investment objective is to provide a high level of current income. The Trust, as a secondary objective, also seeks the preservation of capital to the extent consistent with its primary objective of high current income. The Trust's investment adviser is BlackRock Advisors, LLC (the "Advisor"), and the Advisor's affiliate, BlackRock International Limited (the "Sub-Advisor"), acts as the Trust's sub-adviser.

The Trust has entered into a distribution agreement dated January 9, 2023 (the "Distribution Agreement") with BlackRock Investments, LLC (the "Distributor"), an affiliate of the Advisor, to provide for distribution of the Trust's common shares. The Distributor has entered into a sub-placement agent agreement dated January 9, 2023 (the "Sub-Placement Agent Agreement") with UBS Securities LLC (the "Sub-Placement Agent") with respect to the Trust relating to the common shares offered by this Prospectus Supplement and the accompanying Prospectus. In accordance with the terms of the Sub-Placement Agent Agreement, the Trust may offer and sell its common shares from time to time through the Sub-Placement Agent as sub-placement agent for the offer and sale of its common shares. Under the Investment Company Act, the Trust may not sell any common shares at a price below the current net asset value of such common shares, exclusive of any distributing commission or discount.

Sales of our common shares, if any, under this Prospectus Supplement and the accompanying Prospectus may be made in negotiated transactions or transactions that are deemed to be "at the market" as defined in Rule 415 under the Securities Act of 1933, as amended (the "Securities Act"), including sales made directly on the NYSE or sales made to or through a market maker other than on an exchange.

The Trust will compensate the Distributor with respect to sales of common shares at a commission rate of 1.00% of the gross proceeds of the sale of the Trust's common shares. Out of this commission, the Distributor will compensate the Sub-Placement Agent at a rate of up to 0.80% of the gross sales proceeds of the sale of the Trust's common shares sold by the Sub-Placement Agent. In connection with the sale of the common shares on the Trust's behalf, the Distributor may be deemed to be an "underwriter" within the meaning of the Securities Act and the compensation of the Distributor may be deemed to be underwriting commissions or discounts.

Investing in the Trust's common shares involves certain risks that are described in the "Risks" section beginning on page 29 of the accompanying Prospectus.

NEITHER THE SEC NOR ANY STATE SECURITIES COMMISSION HAS APPROVED OR DISAPPROVED THESE SECURITIES OR DETERMINED IF THIS PROSPECTUS SUPPLEMENT IS TRUTHFUL OR COMPLETE. ANY REPRESENTATION TO THE CONTRARY IS A CRIMINAL OFFENSE.

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This Prospectus Supplement, together with the accompanying Prospectus, sets forth concisely the information about the Trust that a prospective investor should know before investing. You should read this Prospectus Supplement and the accompanying Prospectus, which contain important information, before deciding whether to invest in the common shares. You should retain the accompanying Prospectus and this Prospectus Supplement for future reference. A Statement of Additional Information dated December 28, 2022, as supplemented on January 3, 2023 (the "SAI"), containing additional information about the Trust, has been filed with the Securities and Exchange Commission ("SEC") and, as amended from time to time, is incorporated by reference in its entirety into this Prospectus Supplement and the accompanying Prospectus. This Prospectus Supplement, the accompanying Prospectus and the SAI are part of a "shelf" registration statement filed with the SEC. This Prospectus Supplement describes the specific details regarding this offering, including the method of distribution. If information in this Prospectus Supplement is inconsistent with the accompanying Prospectus or the SAI, you should rely on this Prospectus Supplement. You may call [phone], visit the Trust's website (http://www.blackrock.com) or write to the Trust to obtain, free of charge, copies of the SAI and the Trust's semi-annual and annual reports, as well as to obtain other information about the Trust or to make shareholder inquiries. The SAI, as well as the Trust's semi-annual and annual reports, are also available for free on the SEC's website (http://www.sec.gov). You may also e-mail requests for these documents to [e-mail]. Information contained in, or that can be accessed through, the Trust's website is not part of this Prospectus Supplement or the accompanying Prospectus.

You should not construe the contents of this Prospectus Supplement and the accompanying Prospectus as legal, tax or financial advice. You should consult with your own professional advisors as to the legal, tax, financial or other matters relevant to the suitability of an investment in the Trust.

The Trust's common shares do not represent a deposit or an obligation of, and are not guaranteed or endorsed by, any bank or other insured depository institution, and are not federally insured by the Federal Deposit Insurance Corporation, the Federal Reserve Board or any other government agency.

You should rely only on the information contained or incorporated by reference in this Prospectus Supplement and the accompanying Prospectus. Neither the Trust nor the underwriters have authorized anyone to provide you with different information. The Trust is not making an offer to sell these securities in any jurisdiction where the offer or sale is not permitted. You should not assume that the information contained in this Prospectus Supplement and the accompanying Prospectus is accurate as of any date other than the date of this Prospectus Supplement and the accompanying Prospectus, respectively. Our business, financial condition, results of operations and prospects may have changed since those dates. In this Prospectus Supplement and in the accompanying Prospectus, unless otherwise indicated, "Trust," "us," "our" and "we" refer to BlackRock Floating Rate Income Trust.

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TABLE OF CONTENTS

Prospectus Supplement

CAUTIONARY NOTICE REGARDING FORWARD-LOOKING STATEMENTS . . . . . . . . . . . . . . . . . . S-4 PROSPECTUS SUPPLEMENT SUMMARY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . S-5 SUMMARY OF TRUST EXPENSES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . S-7 USE OF PROCEEDS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . S-9 CAPITALIZATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . S-9 PRICE RANGE OF COMMON SHARES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . S-10 PLAN OF DISTRIBUTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . S-10 LEGAL MATTERS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . S-12 ADDITIONAL INFORMATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . S-12

Prospectus

PROSPECTUS SUMMARY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 SUMMARY OF TRUST EXPENSES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 FINANCIAL HIGHLIGHTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 USE OF PROCEEDS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 THE TRUST . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 DESCRIPTION OF SHARES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 THE TRUST'S INVESTMENTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 LEVERAGE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 RISKS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29 HOW THE TRUST MANAGES RISK . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39 MANAGEMENT OF THE TRUST . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39 NET ASSET VALUE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44 DISTRIBUTIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47 DIVIDEND REINVESTMENT PLAN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48 RIGHTS OFFERINGS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48 TAX MATTERS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49 TAXATION OF HOLDERS OF RIGHTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56

CERTAIN PROVISIONS IN THE AGREEMENT AND DECLARATION OF TRUST AND BYLAWS . . . 56 CLOSED-END FUND STRUCTURE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58 REPURCHASE OF COMMON SHARES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59 PLAN OF DISTRIBUTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59 INCORPORATION BY REFERENCE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61 PRIVACY PRINCIPLES OF THE TRUST . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62

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CAUTIONARY NOTICE REGARDING FORWARD-LOOKING STATEMENTS

This Prospectus Supplement, the accompanying Prospectus and the SAI contain "forward-looking statements." Forward-looking statements can be identified by the words "may," "will," "intend," "expect," "estimate," "continue," "plan," "anticipate," and similar terms and the negative of such terms. Such forward- looking statements may be contained in this Prospectus Supplement as well as in the accompanying Prospectus. By their nature, all forward-looking statements involve risks and uncertainties, and actual results could differ materially from those contemplated by the forward-looking statements. Several factors that could materially affect our actual results are the performance of the portfolio of securities we hold, the price at which our shares will trade in the public markets and other factors discussed in our periodic filings with the SEC.

Although we believe that the expectations expressed in our forward-looking statements are reasonable, actual results could differ materially from those projected or assumed in our forward-looking statements. Our future financial condition and results of operations, as well as any forward-looking statements, are subject to change and are subject to inherent risks and uncertainties, such as those disclosed in the "Risks" section of the accompanying Prospectus. All forward-looking statements contained or incorporated by reference in this Prospectus Supplement or the accompanying Prospectus are made as of the date of this Prospectus Supplement or the accompanying Prospectus, as the case may be. Except for our ongoing obligations under the federal securities laws, we do not intend, and we undertake no obligation, to update any forward-looking statement. The forward- looking statements contained in this Prospectus Supplement, the accompanying Prospectus and the SAI are excluded from the safe harbor protection provided by Section 27A of the Securities Act.

Currently known risk factors that could cause actual results to differ materially from our expectations include, but are not limited to, the factors described in the "Risks" section of the accompanying Prospectus. We urge you to review carefully those sections for a more detailed discussion of the risks of an investment in our common shares.

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PROSPECTUS SUPPLEMENT SUMMARY

The following summary is qualified in its entirety by reference to the more detailed information included elsewhere in this Prospectus Supplement and in the accompanying Prospectus and in the SAI.

The Trust	The Trust is a diversified, closed-end management investment
	company. The Trust's investment objective is to provide a high level
	of current income. The Trust, as a secondary objective, also seeks the
	preservation of capital to the extent consistent with its primary
	objective of high current income. The Trust is not intended as, and
	you should not construe it to be, a complete investment program.
	There can be no assurance that the Trust's investment objectives will
	be achieved or that the Trust's investment program will be
	successful. The Trust's common shares are listed for trading on the
	NYSE under the symbol "BGT."
Investment Advisor and	BlackRock Advisors, LLC (previously defined as the "Advisor") acts
Sub-Advisor	as the Trust's investment adviser and its affiliate, BlackRock
	International Limited (previously defined as the "Sub-Advisor"), acts
	as the Trust's sub-adviser. The Advisor receives an annual fee,
	payable monthly, in an amount equal to 0.75% of the average weekly
	value of the Trust's Managed Assets. The Advisor, and not the Trust,
	pays an annual sub-advisory fee to the Sub-Advisor equal to a
	percentage of the management fee received by the Advisor from the
	Trust with respect to the average daily value of the Managed Assets
	of the Trust allocated to the Sub-Advisor. "Managed Assets" means
	the total assets of the Trust (including any assets attributable to
	money borrowed for investment purposes) minus the sum of the
	Trust's accrued liabilities (other than money borrowed for
	investment purposes).
The Offering	The Trust has entered into the Distribution Agreement with the
	Distributor to provide for distribution of the Trust's common shares.
	The Distributor has entered into the Sub-Placement Agent
	Agreement with the Sub-Placement Agent with respect to the Trust
	relating to the common shares offered by this Prospectus Supplement
	and the accompanying Prospectus. In accordance with the terms of
	the Sub-Placement Agent Agreement, the Trust may offer and sell its
	common shares from time to time through the Sub-Placement Agent
	as sub-placement agent for the offer and sale of its common shares.
	The Trust will compensate the Distributor with respect to sales of
	common shares at a commission rate of 1.00% of the gross proceeds
	of the sale of the Trust's common shares. Out of this commission, the
	Distributor will compensate the Sub-Placement Agent at a rate of up
	to 0.80% of the gross sales proceeds of the sale of the Trust's
	common shares sold by the Sub-Placement Agent.
	The provisions of the Investment Company Act generally require
	that the public offering price of common shares (less any
	underwriting commissions and discounts) must equal or exceed the
	net asset value per share of a company's common shares (calculated
	within 48 hours of pricing).
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