Supplemental Prospectus - Form 424B7

Filed pursuant to 424(b)(7)
Registration Statement No. 333-268404

PROSPECTUS SUPPLEMENT

(To Prospectus dated November 16, 2022)

BROOKDALE SENIOR LIVING INC.

54,968,244 SHARES OF COMMON STOCK OFFERED BY THE SELLING SECURITYHOLDERS

This prospectus supplement relates to the offer and resale from time to time by the Selling Securityholders named in this prospectus supplement (the "Selling Securityholders"), or their permitted transferees of up to 54,968,244 shares of common stock of the Company, par value $0.01 per share (the "common stock"). All of the shares of common stock being offered for resale by the Selling Securityholders pursuant to this prospectus supplement are shares of common stock issuable to the Selling Securityholders upon conversion of the Company's outstanding 3.50% Convertible Senior Notes due 2029 (the "Notes") issued by us in a private placement completed on October 3, 2024.

The conversion rate, and therefore the number of shares of common stock issuable to the Selling Securityholders upon conversion of the Notes, is subject to adjustment in certain circumstances. Accordingly, the number of shares of common stock issuable with respect to the Notes may increase or decrease.

Our registration of the securities covered by this prospectus supplement does not mean that the Selling Securityholders will offer or sell any of the securities. The Selling Securityholders may offer and sell the securities covered by this prospectus supplement in a number of different ways and at varying prices. We provide more information about how the Selling Securityholders may sell the shares of common stock in the section entitled "Plan of Distribution."

We will not receive any proceeds from the sale of shares of common stock by the Selling Securityholders pursuant to this prospectus supplement. However, we will pay the expenses, other than underwriting discounts and commissions, incurred by the Selling Securityholders in connection with the registration of the securities covered by this prospectus supplement.

Our common stock is listed on the New York Stock Exchange under the trading symbol "BKD." On October 22, 2024, the last reported sale price of our common stock was $6.18 per share.

Investing in our securities involves risks. You should read the section entitled "Risk Factors" beginning on page S-2 of this prospectus supplement and in the documents incorporated by reference herein, before buying our securities.

Neither the Securities and Exchange Commission (the "SEC") nor any state securities commission has approved or disapproved of these securities or determined if this prospectus supplement is truthful or complete. Any representation to the contrary is a criminal offense.

The date of this prospectus supplement is October 23, 2024.

TABLE OF CONTENTS

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ABOUT THIS PROSPECTUS SUPPLEMENT

This document consists of two parts. The first part is this prospectus supplement, which describes the specific terms of this offering and also adds to and updates information contained in the accompanying prospectus and the documents incorporated by reference. The second part is the accompanying prospectus, which gives more general information, some of which may not apply to this offering.

To the extent there is a conflict between the information contained in this prospectus supplement and the information contained in the accompanying prospectus or any document incorporated by reference therein filed prior to the date of this prospectus supplement, you should rely on the information in this prospectus supplement.

Unless we specifically state otherwise, the information in this prospectus supplement and the accompanying prospectus, including the documents incorporated by reference herein and therein, does not give effect to the transactions contemplated herein. You should rely only on the information contained or incorporated by reference in this prospectus supplement.

Neither we nor the Selling Securityholders have authorized anyone to provide you with any information other than that contained in or incorporated by reference into this prospectus supplement and the accompanying prospectus prepared by or on behalf of us. Neither we nor the Selling Securityholders take responsibility for, and can provide no assurance as to the reliability of, any other information that others may give you. Neither we nor the Selling Securityholders are making an offer to sell these securities in any jurisdiction where the offer or sale is not authorized or in which the person making such offer or solicitation is not qualified to do so or to anyone to whom it is unlawful to make an offer or solicitation.

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WHERE YOU CAN FIND MORE INFORMATION

We file annual, quarterly and current reports, proxy statements and other information with the SEC under the Securities Exchange Act of 1934, as amended (the "Exchange Act"). Our SEC filings are available to the public at the SEC's website at www.sec.gov.

The SEC allows us to "incorporate by reference" information into this prospectus supplement and any accompanying prospectus, which means that we can disclose important information to you by referring you to another document filed separately with the SEC. The information incorporated by reference is deemed to be part of this prospectus supplement and the accompanying prospectus, except for any information superseded by information contained in any subsequently filed document deemed incorporated by reference or any free writing prospectus prepared by or on behalf of us. This prospectus supplement and the accompanying prospectus incorporate by reference the documents set forth below that we have previously filed with the SEC (other than information deemed furnished and not filed in accordance with SEC rules, including Items 2.02 and 7.01 of Form 8-K):

All documents filed by us pursuant to Sections 13(a), 13(c), 14 or 15(d) of the Exchange Act after the date of this prospectus supplement and before the termination of the offering also shall be deemed to be incorporated herein by reference. We are not, however, incorporating by reference any documents or portions thereof that are not deemed "filed" with the SEC, including any information furnished pursuant to Items 2.02 or 7.01 of Form 8-K.

If requested, we will provide to each person, including any beneficial owner, to whom a prospectus is delivered, a copy of any or all of the information that has been incorporated by reference in the prospectus but not delivered with the prospectus. Exhibits to the filings will not be sent, however, unless those exhibits have specifically been incorporated by reference into such documents. To obtain a copy of these filings at no cost, you may write or telephone us at the following address:

Brookdale Senior Living Inc., Attn: Secretary

105 Westwood Place, Suite 400

Brentwood, Tennessee 37027

(615) 221-2250

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CAUTIONARY STATEMENT REGARDING FORWARD-LOOKING STATEMENTS

Certain statements in this prospectus supplement, the accompanying prospectus and the documents incorporated by reference may constitute forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995. These forward-looking statements are subject to various risks and uncertainties and include all statements that are not historical statements of fact and those regarding our intent, belief or expectations. Forward-looking statements are generally identifiable by use of forward-looking terminology such as "may," "will," "should," "could," "would," "potential," "intend," "expect," "endeavor," "seek," "anticipate," "estimate," "believe," "project," "predict," "continue," "plan," "target," or other similar words or expressions. These forward-looking statements are based on certain assumptions and expectations, and our ability to predict results or the actual effect of future plans or strategies is inherently uncertain. Although we believe that expectations reflected in any forward-looking statements are based on reasonable assumptions, we can give no assurance that our assumptions or expectations will be attained, and actual results and performance could differ materially from those projected. Factors which could have a material adverse effect on our operations and future prospects or which could cause events or circumstances to differ from the forward-looking statements include, but are not limited to, events which adversely affect the ability of seniors to afford resident fees, including downturns in the economy, housing market, consumer confidence, or the equity markets and unemployment among resident family members; changes in reimbursement rates, methods, or timing under governmental reimbursement programs including the Medicare and Medicaid programs; the effects of senior housing construction and development, lower industry occupancy, and increased competition; conditions of housing markets, regulatory changes, acts of nature, and the effects of climate change in geographic areas where we are concentrated; terminations of our resident agreements and vacancies in the living spaces we lease; failure to maintain the security and functionality of our information systems, to prevent a cybersecurity attack or breach, or to comply with applicable privacy and consumer protection laws, including HIPAA; our ability to complete our capital expenditures in accordance with our plans; our ability to identify and pursue development, investment, and acquisition opportunities and our ability to successfully integrate acquisitions; competition for the acquisition of assets; our ability to complete pending or expected disposition, acquisition, or other transactions on agreed upon terms or at all, including in respect of the satisfaction of closing conditions, the risk that regulatory approvals are not obtained or are subject to unanticipated conditions, and uncertainties as to the timing of closing, and our ability to identify and pursue any such opportunities in the future; risks related to the implementation of our strategy, including initiatives undertaken to execute on our strategic priorities and their effect on our results; the impacts of the COVID-19 pandemic, including on the nation's economy and debt and equity markets and the local economies in our markets, and on us and our business, results of operations, cash flow, revenue, expenses, liquidity, and our strategic initiatives, including plans for future growth, which will depend on many factors, some of which cannot be foreseen, including the pace and consistency of recovery from the pandemic and any resurgence or variants of the disease; limits on our ability to use net operating loss carryovers to reduce future tax payments; delays in obtaining regulatory approvals; disruptions in the financial markets or decreases in the appraised values or performance of our communities that affect our ability to obtain financing or extend or refinance debt as it matures and our financing costs; our ability to generate sufficient cash flow to cover required interest, principal, and long-term lease payments and to fund our planned capital projects; the effect of any non-compliance with any of our debt or lease agreements (including the financial or other covenants contained therein), including the risk of lenders or lessors declaring a cross default in the event of our non-compliance with any such agreements and the risk of loss of our property securing leases and indebtedness due to any resulting lease terminations and foreclosure actions; the inability to renew, restructure, or extend leases, or exercise purchase options at or prior to the end of any existing lease term; the effect of our indebtedness and long-term leases on our liquidity and our ability to operate our business; increases in market interest rates that increase the costs of our debt obligations; our ability to obtain additional capital on terms acceptable to us; departures of key officers and potential disruption caused by changes in management; increased competition for, or a shortage of, associates, wage pressures resulting from increased competition, low unemployment levels, minimum wage increases and changes in overtime laws, and union activity; environmental contamination at any of our communities; failure to comply with existing environmental laws; an adverse determination or resolution of complaints filed against us, including putative class action complaints and the

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frequency and magnitude of legal actions and liability claims that may arise due to COVID-19 or our response efforts; negative publicity with respect to any lawsuits, claims, or other legal or regulatory proceedings; costs to respond to, and adverse determinations resulting from, government inquiries, reviews, audits and investigations; the cost and difficulty of complying with increasing and evolving regulation, including new disclosure obligations; changes in, or our failure to comply with, employment-related laws and regulations; the risks associated with current global economic conditions and general economic factors on us and our business partners such as inflation, commodity costs, fuel and other energy costs, competition in the labor market, costs of salaries, wages, benefits, and insurance, interest rates, tax rates, geopolitical tensions or conflicts, and uncertainty surrounding federal elections; the impact of seasonal contagious illness or an outbreak of COVID-19 or other contagious disease in the markets in which we operate; actions of activist stockholders, including a proxy contest; as well as other risks detailed from time to time in our filings with the SEC, including those set forth under "Risk Factors" included elsewhere in this prospectus supplement, the accompanying prospectus and in the documents incorporated by reference in this prospectus supplement and the accompanying prospectus. When considering forward-looking statements, you should keep in mind the risk factors and other cautionary statements in such SEC filings and this prospectus supplement. Readers are cautioned not to place undue reliance on any of these forward-looking statements, which reflect management's views as of the date of this prospectus supplement. We cannot guarantee future results, levels of activity, performance or achievements, and, except as required by law, we expressly disclaim any obligation to release publicly any updates or revisions to any forward-looking statements contained in this prospectus supplement to reflect any change in our expectations with regard thereto or change in events, conditions or circumstances on which any statement is based.

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RISK FACTORS

You should consider the specific risks described in our most recent Annual Report on Form 10-K (together with any material changes thereto contained in subsequently filed Quarterly Reports on Form 10-Q) and any risk factors set forth in our other filings with the SEC, before making an investment decision. Each of the risks described in these documents could materially and adversely affect our business, financial condition, results of operations and prospects, and could result in a partial or complete loss of your investment. See "Where You Can Find More Information" in this prospectus supplement.

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USE OF PROCEEDS

All of the shares of common stock offered by the Selling Securityholders pursuant to this prospectus supplement will be sold by the Selling Securityholders for their respective accounts. We will not receive any of the proceeds from these sales.

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SELLING SECURITYHOLDERS

This prospectus supplement relates to the resale by the Selling Securityholders from time to time of up to 54,968,244 shares of our common stock, issuable by us upon conversion of the Notes.

On September 30, 2024, we entered into exchange and subscription agreements with certain investors, pursuant to which we agreed to sell the Notes pursuant to the terms of an indenture between us and Equiniti Trust Company, LLC, dated as of October 3, 2024. The Notes were initially convertible into a maximum of 54,968,244 shares of common stock and were issued in a transaction exempt from the registration requirements of the Securities Act of 1933, as amended (the "Securities Act"). Upon conversion of any Notes, we will be obligated to settle such conversion by paying or delivering, as the case may be, cash, shares of our common stock or a combination of cash and shares of our common stock, at our election. We will not be obligated to deliver any shares of common stock to any holder upon any conversion of the Notes to the extent that immediately following such conversion such holder would beneficially own a number of shares of our common stock in excess of 19.9% of the total number of shares of our common stock issued and outstanding immediately following such conversion. In addition, we entered into a registration rights agreement with certain investors, dated October 3, 2024, pursuant to which we agreed to use commercially reasonable efforts to file a prospectus supplement or shelf registration statement with the SEC on or prior to October 25, 2024, providing for the registration and sale of the shares of common stock issuable upon conversion of the Notes. We have agreed with the Selling Securityholders to use commercially reasonable efforts to cause the registration statement of which this prospectus supplement constitutes a part to become effective and to remain continuously effective until the earlier of (1) the date on which all of the shares included in the registration statement have been sold pursuant to such registration statement or pursuant to Rule 144 of the Securities Act, (2) the date upon which there are no Notes or shares issued upon conversion of the Notes held by investors or (3) the date on which all of the shares included in such registration statement may be immediately sold to the public without registration or restriction (including without limitation as to volume by each holder thereof), and without compliance with any current public information requirement pursuant to Rule 144 of the Securities Act.

Beneficial ownership is determined in accordance with the rules of the SEC and accordingly, the number of shares of common stock beneficially owned by each Selling Securityholder in this section does not include the shares of our common stock issuable upon conversion of the Notes. These rules generally attribute beneficial ownership of securities to persons who possess sole or shared voting power or investment power with respect to such securities, including the right to acquire such voting or investment power within 60 days of the date of determination through the exercise of any option, warrant or other right. Except as otherwise indicated, all persons listed below have sole voting and investment power with respect to the shares beneficially owned by them.

The information in the below table (other than the percentages of our outstanding common stock beneficially owned) in respect of each Selling Securityholder was furnished by or on behalf of such Selling Securityholder and is as of October 15, 2024. Except as may be noted in this section, no Selling Securityholder has, or has had within the past three years, any material relationship with us or any of our affiliates.

We will supplement or amend this prospectus supplement if applicable to include additional Selling Securityholders upon provision of all required information to us and subject to the terms of any relevant agreement between us and the Selling Securityholder.

The Selling Securityholders are not obligated to sell any of the shares of common stock offered by this prospectus supplement. Because the Selling Securityholders identified in the table may sell some or all of the shares of common stock owned by it that are included in this prospectus supplement, and because there are currently no agreements, arrangements or understandings with respect to the sale of any such shares of common stock, no estimate can be given as to the number of shares covered by this prospectus supplement that will be held by the Selling Securityholders upon termination of this offering. Therefore, for the purposes of the following table we have assumed that the Selling Securityholders will sell all of the shares of common stock beneficially

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owned by it that are covered by this prospectus supplement, but will not sell any other shares of common stock that they may currently own.

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PLAN OF DISTRIBUTION

The Selling Securityholders, which as used herein includes donees, pledgees, transferees or other successors-in-interest selling shares of common stock or interests in shares of common stock received after the date of this prospectus supplement from a Selling Securityholder as a gift, pledge, partnership distribution or other transfer, may, from time to time, sell, transfer or otherwise dispose of any or all of their shares of common stock or interests in shares of common stock on any stock exchange, market or trading facility on which the shares are traded or in private transactions. These dispositions may be at fixed prices, at prevailing market prices at the time of sale, at prices related to the prevailing market price, at varying prices determined at the time of sale, or at negotiated prices.

The Selling Securityholders may use any one or more of the following methods when disposing of shares or interests therein:

The Selling Securityholders may, from time to time, pledge or grant a security interest in some or all of the shares of common stock owned by them and, if they default in the performance of their secured obligations, the pledgees or secured parties may offer and sell the shares of common stock, from time to time, under this prospectus supplement, or under an amendment to this prospectus supplement under Rule 424(b)(3) or other applicable provision of the Securities Act, amending the list of Selling Securityholders to include the pledgee, transferee or other successors in interest as Selling Securityholders under this prospectus supplement. The Selling Securityholders also may transfer the shares of common stock in other circumstances, in which case the transferees, pledgees or other successors in interest will be the selling beneficial owners for purposes of this prospectus supplement.

In connection with the sale of our common stock or interests therein, the Selling Securityholders may enter into hedging transactions with broker-dealers or other financial institutions, which may in turn engage in short sales of the common stock in the course of hedging the positions they assume. The Selling Securityholders may also sell shares of our common stock short and deliver these securities to close out their short positions, or loan or pledge the common stock to broker-dealers that in turn may sell these securities. The Selling Securityholders may also enter into option or other transactions with broker-dealers or other financial institutions or the creation of one or more derivative securities which require the delivery to such broker-dealer or other financial institution of shares offered by this prospectus supplement, which shares such broker-dealer or other financial institution may resell pursuant to this prospectus supplement (as supplemented or amended to reflect such transaction).

The Selling Securityholders may engage brokers and dealers, and any brokers or dealers may arrange for other brokers or dealers to participate in effecting sales of our common stock or interests therein. These brokers,

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dealers or underwriters may act as principals, or as an agent of a Selling Securityholder. Broker-dealers may agree with a Selling Securityholder to sell a specified number of the shares at a stipulated price per share. If the broker-dealer is unable to sell the shares acting as agent for a Selling Securityholder, it may purchase as principal any unsold shares at the stipulated price. Broker-dealers who acquire the shares as principals may thereafter resell the shares from time to time in transactions in any stock exchange, market or trading facility on which the shares are then listed or traded, at prices and on terms then prevailing at the time of sale, at prices related to the then-current market price or in negotiated transactions. Broker-dealers may use block transactions and sales to and through broker-dealers, including transactions of the nature described above.

The aggregate proceeds to the Selling Securityholders from the sale of the common stock offered by them will be the purchase price of the common stock less discounts or commissions, if any. Each of the Selling Securityholders reserves the right to accept and, together with their agents from time to time, to reject, in whole or in part, any proposed purchase of common stock to be made directly or through agents. We will not receive any of the proceeds from this offering.

The Selling Securityholders also may resell all or a portion of the shares in open market transactions in reliance upon Rule 144 under the Securities Act, provided that they meet the criteria and conform to the requirements of that rule.

Any underwriters, broker-dealers or agents that participate in the sale of the common stock or interests therein may be "underwriters" within the meaning of Section 2(11) of the Securities Act. Any discounts, commissions, concessions or profit they earn on any resale of the shares may be underwriting discounts and commissions under the Securities Act.

To the extent required, the shares of our common stock to be sold, the names of the Selling Securityholders, the respective purchase prices and public offering prices, the names of any agents, dealer or underwriter, and any applicable commissions or discounts with respect to a particular offer will be set forth in an accompanying prospectus supplement or, if appropriate, a post-effective amendment to the registration statement that includes this prospectus supplement.

In order to comply with the securities laws of some states, if applicable, the common stock may be sold in these jurisdictions only through registered or licensed brokers or dealers.

We have advised the Selling Securityholders that the anti-manipulation rules of Regulation M under the Exchange Act, may apply to sales of shares in the market and to the activities of the Selling Securityholders and their affiliates. In addition, to the extent applicable, we will make copies of this prospectus supplement (as it may be supplemented or amended from time to time) available to the Selling Securityholders for the purpose of satisfying the prospectus delivery requirements of the Securities Act. The Selling Securityholders may indemnify any broker-dealer that participates in transactions involving the sale of the shares against certain liabilities, including liabilities arising under the Securities Act.

We have agreed to indemnify the Selling Securityholders against liabilities, including liabilities under the Securities Act and state securities laws, relating to the registration of the shares offered by this prospectus supplement.

We have agreed with the Selling Securityholders to use commercially reasonable efforts to cause the registration statement of which this prospectus supplement constitutes a part to become effective and to remain continuously effective until the earlier of (1) the date on which all of the shares included in the registration statement have been sold pursuant to such registration statement or pursuant to Rule 144 of the Securities Act, (2) the date upon which there are no Notes or shares issued upon conversion of the Notes held by investors or (3) the date on which all of the shares included in such registration statement may be immediately sold to the public without registration or restriction (including without limitation as to volume by each holder thereof), and without compliance with any current public information requirement pursuant to Rule 144 of the Securities Act.

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LEGAL MATTERS

The validity of the issuance of the shares of common stock offered hereby will be passed upon by Skadden, Arps, Slate, Meagher & Flom, New York, New York. Any underwriters will be advised about legal matters by their own counsel, which will be named in a prospectus supplement.

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EXPERTS

The consolidated financial statements of Brookdale Senior Living Inc. appearing in Brookdale Senior Living Inc.'s Annual Report (Form 10-K) for the year ended December 31, 2023 and the effectiveness of Brookdale Senior Living Inc.'s internal control over financial reporting as of December 31, 2023, have been audited by Ernst & Young LLP, independent registered public accounting firm, as set forth in their reports thereon, included therein, and incorporated herein by reference. Such consolidated financial statements are incorporated herein by reference in reliance upon such reports given on the authority of such firm as experts in accounting and auditing.

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Prospectus

BROOKDALE SENIOR LIVING INC.

Common Stock

Preferred Stock

Depositary Shares

Debt Securities

Warrants

Subscription Rights

Purchase Contracts

and

Purchase Units

We may offer, issue and sell, together or separately:

We will provide the specific prices and terms of these securities in one or more supplements to this prospectus at the time of offering. You should read this prospectus and the accompanying prospectus supplement carefully before you make your investment decision.

This prospectus may not be used to sell securities unless accompanied by a prospectus supplement.

Investing in our securities involves a number of risks. See "Risk Factors" on page 6 before you make your investment decision.

We may offer securities through underwriting syndicates managed or co-managed by one or more underwriters or dealers, through agents or directly to purchasers, on a continuous or delayed basis. These securities also may be sold by selling securityholders. If required, the prospectus supplement for each offering of securities will describe the plan of distribution for that offering. For general information about the distribution of securities offered, please see "Plan of Distribution" in this prospectus.

Our common stock is listed on the New York Stock Exchange (the "NYSE") under the trading symbol "BKD." Each prospectus supplement will indicate whether the securities offered thereby will be listed on any securities exchange.

Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of these securities or determined if this prospectus or any accompanying prospectus supplement is truthful or complete. Any representation to the contrary is a criminal offense.

The date of this prospectus is November 16, 2022.

TABLE OF CONTENTS

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ABOUT THIS PROSPECTUS

This prospectus is part of an "automatic shelf" registration statement that we filed with the Securities and Exchange Commission (the "SEC") as a "well-known seasoned issuer" as defined in Rule 405 under the Securities Act of 1933, as amended (the "Securities Act"), using a "shelf" registration process. Under this process, we and selling securityholders may sell from time to time any combination of the securities described in this prospectus. This prospectus only provides you with a general description of the securities that we may offer. Each time we or selling securityholders sell securities, we will provide a supplement to this prospectus that contains specific information about the terms of that offering, including the specific amounts, prices and terms of the securities offered. The prospectus supplement may also add, update or change information contained in this prospectus. You should carefully read both this prospectus, any accompanying prospectus supplement and any free writing prospectus prepared by or on behalf of us, together with the additional information described under the heading "Where You Can Find More Information."

We have not authorized anyone to provide you with any information other than that contained in or incorporated by reference into this prospectus, any accompanying prospectus supplement and any free writing prospectus prepared by or on behalf of us. We take no responsibility for, and can provide no assurance as to the reliability of, any other information that others may give you. We are not making offers to sell the securities in any jurisdiction in which an offer or solicitation is not authorized or in which the person making such offer or solicitation is not qualified to do so or to anyone to whom it is unlawful to make an offer or solicitation.

The information in this prospectus is accurate as of the date on the front cover. You should not assume that the information contained in this prospectus is accurate as of any other date.

When used in this prospectus, the terms "Brookdale," the "Company," "we," "our" and "us" refer to Brookdale Senior Living Inc. and its consolidated subsidiaries, unless otherwise specified or the context otherwise requires.

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WHERE YOU CAN FIND MORE INFORMATION

We file annual, quarterly and current reports, proxy statements and other information with the SEC under the Securities Exchange Act of 1934, as amended (the "Exchange Act"). Our SEC filings are available to the public at the SEC's website at www.sec.gov.

The SEC allows us to "incorporate by reference" information into this prospectus and any accompanying prospectus supplement, which means that we can disclose important information to you by referring you to another document filed separately with the SEC. The information incorporated by reference is deemed to be part of this prospectus and any accompanying prospectus supplement, except for any information superseded by information contained directly in this prospectus, any accompanying prospectus supplement, any subsequently filed document deemed incorporated by reference or any free writing prospectus prepared by or on behalf of us. This prospectus and any accompanying prospectus supplement incorporate by reference the documents set forth below that we have previously filed with the SEC (other than information deemed furnished and not filed in accordance with SEC rules, including Items 2.02 and 7.01 of Form 8-K).

All documents filed by us pursuant to Sections 13(a), 13(c), 14 or 15(d) of the Exchange Act after the date of this prospectus and before the termination of the offering also shall be deemed to be incorporated herein by reference. We are not, however, incorporating by reference any documents or portions thereof that are not deemed "filed" with the SEC, including any information furnished pursuant to Items 2.02 or 7.01 of Form 8-K.

If requested, we will provide to each person, including any beneficial owner, to whom a prospectus is delivered, a copy of any or all of the information that has been incorporated by reference in the prospectus but not delivered with the prospectus. Exhibits to the filings will not be sent, however, unless those exhibits have specifically been incorporated by reference into such documents. To obtain a copy of these filings at no cost, you may write or telephone us at the following address:

Brookdale Senior Living Inc., Attn: Secretary

111 Westwood Place, Suite 400

Brentwood, Tennessee 37027

(615) 221-2250

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CAUTIONARY NOTE REGARDING FORWARD-LOOKING STATEMENTS

Certain statements in this prospectus, any accompanying prospectus supplements and the documents incorporated by reference may constitute forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995. These forward-looking statements are subject to various risks and uncertainties and include all statements that are not historical statements of fact and those regarding our intent, belief or expectations. Forward-looking statements are generally identifiable by use of forward-looking terminology such as "may," "will," "should," "could," "would," "potential," "intend," "expect," "endeavor," "seek," "anticipate," "estimate," "believe," "project," "predict," "continue," "plan," "target," or other similar words or expressions. These forward-looking statements are based on certain assumptions and expectations, and our ability to predict results or the actual effect of future plans or strategies is inherently uncertain. Although we believe that expectations reflected in any forward-looking statements are based on reasonable assumptions, we can give no assurance that our assumptions or expectations will be attained, and actual results and performance could differ materially from those projected. Factors which could have a material adverse effect on our operations and future prospects or which could cause events or circumstances to differ from the forward-looking statements include, but are not limited to, the impacts of the COVID-19 pandemic, including the response efforts of federal, state, and local government authorities, businesses, individuals, and us on our business, results of operations, cash flow, revenue, expenses, liquidity, and our strategic initiatives, including plans for future growth, which will depend on many factors, some of which cannot be foreseen, including the duration, severity, and breadth of the pandemic and any resurgence or variants of the disease, the impact of COVID-19 on the nation's economy and debt and equity markets and the local economies in our markets, the development, availability, utilization, and efficacy of COVID-19 testing, therapeutic agents, and vaccines and the prioritization of such resources among businesses and demographic groups, government financial and regulatory relief efforts that may become available to business and individuals, including our ability to qualify for and satisfy the terms and conditions of financial relief, perceptions regarding the safety of senior living communities during and after the pandemic, changes in demand for senior living communities and our ability to adapt our sales and marketing efforts to meet that demand, the impact of COVID-19 on our residents' and their families' ability to afford our resident fees, including due to changes in unemployment rates, consumer confidence, housing markets, and equity markets caused by COVID-19, changes in the acuity levels of our new residents, the disproportionate impact of COVID-19 on seniors generally and those residing in our communities, the duration and costs of our response efforts, including increased equipment, supplies, labor, litigation, testing, vaccination clinic, health plan, and other expenses, greater use of contract labor and overtime due to COVID-19 and general labor market conditions, the impact of COVID-19 on our ability to complete financings and refinancings of various assets, or other transactions or to generate sufficient cash flow to cover required debt, interest, and lease payments and to satisfy financial and other covenants in our debt and lease documents, increased regulatory requirements, including the costs of unfunded, mandatory testing of residents and associates and provision of test kits to our health plan participants, increased enforcement actions resulting from COVID-19, government action that may limit our collection or discharge efforts for delinquent accounts, and the frequency and magnitude of legal actions and liability claims that may arise due to COVID-19 or our response efforts; events which adversely affect the ability of seniors to afford resident fees, including downturns in the economy, housing market, consumer confidence, or the equity markets and unemployment among resident family members; changes in reimbursement rates, methods, or timing under governmental reimbursement programs including the Medicare and Medicaid programs; the effects of senior housing construction and development, lower industry occupancy (including due to the pandemic), and increased competition; conditions of housing markets, regulatory changes, acts of nature, and the effects of climate change in geographic areas where we are concentrated; terminations of our resident agreements and vacancies in the living spaces we lease, including due to the pandemic; failure to maintain the security and functionality of our information systems, to prevent a cybersecurity attack or breach, or to comply with applicable privacy and consumer protection laws, including HIPAA; our ability to complete our capital expenditures in accordance with our plans; our ability to identify and pursue development, investment, and acquisition opportunities and our ability to successfully integrate acquisitions; competition for the acquisition of assets; our ability to complete pending or expected disposition, acquisition, or other transactions on agreed upon terms or at all, including in respect of the satisfaction of closing conditions, the risk that regulatory approvals are

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not obtained or are subject to unanticipated conditions, and uncertainties as to the timing of closing, and our ability to identify and pursue any such opportunities in the future; risks related to the implementation of our strategy, including initiatives undertaken to execute on our strategic priorities and their effect on our results; limits on our ability to use net operating loss carryovers to reduce future tax payments; delays in obtaining regulatory approvals; disruptions in the financial markets or decreases in the appraised values or performance of our communities that affect our ability to obtain financing or extend or refinance debt as it matures and our financing costs; our ability to generate sufficient cash flow to cover required interest, principal, and long-term lease payments and to fund our planned capital projects; the effect of our non-compliance with any of our debt or lease agreements (including the financial covenants contained therein), including the risk of lenders or lessors declaring a cross default in the event of our non-compliance with any such agreements and the risk of loss of our property securing leases and indebtedness due to any resulting lease terminations and foreclosure actions; the effect of our indebtedness and long-term leases on our liquidity and our ability to operate our business; increases in market interest rates that increase the costs of our debt obligations; our ability to obtain additional capital on terms acceptable to us; departures of key officers and potential disruption caused by changes in management; increased competition for, or a shortage of, associates (including due to the pandemic or general labor market conditions), wage pressures resulting from increased competition, low unemployment levels, minimum wage increases and changes in overtime laws, and union activity; environmental contamination at any of our communities; failure to comply with existing environmental laws; an adverse determination or resolution of complaints filed against us, including putative class action complaints; the cost and difficulty of complying with increasing and evolving regulation; costs to respond to, and adverse determinations resulting from, government reviews, audits and investigations; changes in, or our failure to comply with, employment-related laws and regulations; unanticipated costs to comply with legislative or regulatory developments; the risks associated with current global economic conditions and general economic factors such as inflation, the consumer price index, commodity costs, fuel and other energy costs, competition in the labor market, costs of salaries, wages, benefits, and insurance, interest rates, and tax rates; the impact of seasonal contagious illness or an outbreak of COVID-19 or other contagious disease in the markets in which we operate; actions of activist stockholders, including a proxy contest; as well as other risks detailed from time to time in our filings with the Securities and Exchange Commission, including those set forth under "Risk Factors" included elsewhere in this prospectus and in the documents incorporated by reference in this prospectus. When considering forward-looking statements, you should keep in mind the risk factors and other cautionary statements in such SEC filings, press releases and other communications. Readers are cautioned not to place undue reliance on any of these forward-looking statements, which reflect management's views as of the date of this prospectus. We cannot guarantee future results, levels of activity, performance or achievements, and, except as required by law, we expressly disclaim any obligation to release publicly any updates or revisions to any forward-looking statements contained herein to reflect any change in our expectations with regard thereto or change in events, conditions or circumstances on which any statement is based.

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THE COMPANY

We are the nation's premier operator of senior living communities, operating and managing 672 communities in 41 states as of September 30, 2022, with the ability to serve more than 60,000 residents. We offer our residents access to a broad continuum of services across the most attractive sectors of the senior living industry. We operate and manage independent living, assisted living, memory care, and continuing care retirement communities ("CCRCs").

Our goal is to be the first choice in senior living by being the nation's most trusted and effective senior living provider and employer. Our senior living communities and our comprehensive network help to provide seniors with care and services in an environment that feels like home. Our expertise in healthcare, hospitality, and real estate provides residents with opportunities to improve wellness, pursue passions, and stay connected with friends and loved ones. By providing residents with a range of service options as their needs change, we provide greater continuity of care, enabling seniors to age-in-place, which we believe enables them to maintain residency with us for a longer period of time. The ability of residents to age-in-place is also beneficial to our residents' families who are concerned with care decisions for their elderly relatives.

Our principal executive offices are located at 111 Westwood Place, Suite 400, Brentwood, Tennessee 37027 and our telephone number at that address is (615) 221-2250. Our website address is www.brookdale.com. The information on, or accessible through, our website is not part of this prospectus or any prospectus supplement and should not be relied upon in connection with making any investment decision with respect to the securities offered by this prospectus or any prospectus supplement.

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RISK FACTORS

Investing in our securities involves risk. See the risk factors described in our most recent Annual Report on Form 10-K (together with any material changes thereto contained in subsequently filed Quarterly Reports on Form 10-Q) and those contained in our other filings with the SEC that are incorporated by reference in this prospectus and any accompanying prospectus supplement. Before making an investment decision, you should carefully consider these risks as well as other information we include or incorporate by reference in this prospectus and any accompanying prospectus supplement. These risks could materially affect our business, financial condition or results of operations and cause the value of our securities to decline. You could lose all or part of your investment.

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USE OF PROCEEDS

Unless otherwise set forth in a prospectus supplement, we intend to use the net proceeds of any offering of securities for working capital and other general corporate purposes, which may include the repayment or refinancing of outstanding indebtedness and the financing of future acquisitions. We will have significant discretion in the use of any net proceeds. The net proceeds may be invested temporarily in interest-bearing accounts and short-term interest-bearing securities until they are used for their stated purpose. We may provide additional information on the use of the net proceeds from the sale of the offered securities in an applicable prospectus supplement relating to the offered securities.

Unless set forth in an accompanying prospectus supplement, we will not receive any proceeds in the event that securities are sold by a selling securityholder.

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DESCRIPTION OF SECURITIES

This prospectus contains summary descriptions of the common stock, preferred stock, depositary shares, debt securities, warrants, subscription rights, purchase contracts and purchase units that may be offered and sold from time to time. These summary descriptions are not meant to be complete descriptions of each security. However, at the time of an offering and sale, this prospectus together with the accompanying prospectus supplement will contain the material terms of the securities being offered.

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DESCRIPTION OF CAPITAL STOCK

General

As of the date of this prospectus, our authorized capital stock consists of:

As of November 4, 2022, there were outstanding 186,805,515 shares of common stock (excluding restricted shares and restricted stock units) and no outstanding shares of preferred stock. All of the shares of common stock outstanding on the date of this prospectus are validly issued, fully paid and non-assessable under the Delaware General Corporation Law (the "DGCL").

Set forth below is a summary description of the material terms of our capital stock. This description is qualified in its entirety by reference to our amended and restated certificate of incorporation and amended and restated bylaws.

Common Stock

Each holder of common stock is entitled to one vote for each share of common stock held on all matters submitted to a vote of stockholders. Except as provided with respect to any other class or series of stock, the holders of our common stock possess the exclusive right to vote for the election of directors and for all other purposes. The amended and restated certificate of incorporation does not provide for cumulative voting in the election of directors. The holders of common stock have no preemptive, subscription, redemption or conversion rights. Any shares of common stock sold under this prospectus will be fully paid and non-assessable upon issuance against full payment of the purchase price for such shares.

Subject to any preference rights of holders of our preferred stock that the Company may issue in the future, the holders of our common stock are entitled to receive dividends, if any, declared from time to time by our board of directors out of legally available funds. In the event of our liquidation, dissolution or winding up, the holders of our common stock are entitled to share ratably in all assets remaining after the payment of liabilities, subject to any rights of our holders of preferred stock to prior distribution.

Our common stock is listed and principally traded on the NYSE under the symbol "BKD." On November 15, 2022, the last reported sale price of our common stock on the NYSE was $4.92 per share. As of November 14, 2022, there were 356 holders of record of our common stock.

Preferred Stock

The board of directors has the authority, without action by our stockholders, to issue preferred stock and to fix voting powers for each class or series of preferred stock, and to provide that any class or series may be subject to redemption, entitled to receive dividends, entitled to rights upon dissolution or convertible into, or exchangeable for, shares of any other class or classes of capital stock. The rights with respect to a series or class of preferred stock may be greater than the rights attached to our common stock. It is not possible to state the actual effect of the issuance of any shares of our preferred stock on the rights of holders of our common stock until our board of directors determines the specific rights attached to that preferred stock. The effect of issuing preferred stock could include one or more of the following:

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Anti-Takeover Effects of Delaware Law, Our Amended and Restated Certificate of Incorporation and Our Amended and Restated Bylaws

The following is a summary of certain provisions of our amended and restated certificate of incorporation and amended and restated bylaws that may be deemed to have an anti-takeover effect and may delay, deter or prevent a tender offer or takeover attempt that a stockholder might consider to be in its best interest, including those attempts that might result in a premium over the market price for the shares.

Authorized but Unissued Shares

The authorized but unissued shares of our common stock and our preferred stock will be available for future issuance without approval by our stockholders. These additional shares may be utilized for a variety of corporate purposes, including future public offerings to raise additional capital, corporate acquisitions and employee benefit plans. For our preferred stock, the board of directors is authorized to determine and alter all rights, preferences, privileges, qualifications, limitations and restrictions without limitation. The existence of authorized but unissued shares of our common stock and our preferred stock could render more difficult or discourage an attempt to obtain control over us by means of a proxy contest, tender offer, merger or otherwise.

Delaware Business Combination Statute

We are organized under Delaware law. Some provisions of Delaware law may delay or prevent a transaction that would cause a change in our control.

Our amended and restated certificate of incorporation provides that Section 203 of the DGCL, an anti-takeover law, will not apply to us. In general, this statute prohibits a publicly held Delaware corporation from engaging in a business combination with an interested stockholder for a period of three years after the date of the transaction by which that person became an interested stockholder, unless the business combination is approved in a prescribed manner. For purposes of Section 203, a business combination includes a merger, asset sale or other transaction resulting in a financial benefit to the interested stockholder, and an interested stockholder is a person who, together with affiliates and associates, owns, or within three years prior, did own, 15% or more of voting stock.

Composition of the Board of Directors; Election and Removal of Directors

Our board of directors may consist of not less than three nor more than nine directors. In an uncontested election, directors are elected by a majority of the votes of the shares present in person or represented by proxy and entitled to vote on the election of directors. In a contested election, a plurality voting standard applies to director elections. Since the 2021 annual meeting of stockholders, all directors have been and will be elected for a one-year term expiring at the next annual meeting of stockholders. There is no cumulative voting in the election of directors.

Other Provisions of Our Amended and Restated Certificate of Incorporation and Our Amended and Restated Bylaws

Certain provisions of our amended and restated certificate of incorporation and amended and restated bylaws may make a change in control of the Company more difficult to effect.

Our amended and restated certificate of incorporation and amended and restated bylaws also provide that our stockholders are specifically denied the ability to call a special meeting of the stockholders. Our amended and restated certificate of incorporation and amended and restated bylaws also do not provide for the right of stockholders to act by written consent without a meeting.

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Our amended and restated bylaws require that advance notice must be provided by our stockholders to nominate persons for election to our board of directors as well as to propose actions to be taken at an annual meeting.

The amendment of any of the provisions in our amended and restated certificate of incorporation requires approval by a stockholder vote by the holders of at least a majority of the voting power of the then outstanding voting stock. The bylaws may be amended by the affirmative vote of at least a majority of the whole board of directors or by the affirmative vote of the holders of at least sixty-six and two-thirds percent (66 2/3%) of the voting power of the then outstanding voting stock.

Limitations on Liability and Indemnification of Directors and Officers

Our amended and restated certificate of incorporation provides that our directors will not be personally liable to us or our stockholders for monetary damages for breach of a fiduciary duty as a director, except for:

Our amended and restated certificate of incorporation allows us to indemnify our directors and officers to the fullest extent permitted by Delaware law.

Our amended and restated bylaws allows us to indemnify our directors and officers to the fullest extent permitted by Delaware law. Our amended and restated bylaws also obligate us to advance expenses incurred by a director or officer in advance of the final disposition of any action, suit or proceeding, and permit us to secure insurance on behalf of any officer or director for any liability arising out of his or her actions in that capacity regardless of whether we would otherwise be permitted to indemnify him or her under our amended and restated certificate of incorporation.

We have entered into indemnification agreements with our directors and executive officers. We believe that these bylaw provisions and indemnification agreements are necessary to attract and retain qualified persons as directors and officers.

The limitation of liability and indemnification provisions in our amended and restated certificate of incorporation and amended and restated bylaws may discourage stockholders from bringing a lawsuit against the directors and officers for breach of their fiduciary duty. They may also reduce the likelihood of derivative litigation against the directors and officers, even though an action, if successful, might benefit the Company and its stockholders. Furthermore, a stockholder's investment may be adversely affected to the extent that we pay the costs of settlement and damage.

Insofar as indemnification for liabilities arising under the Securities Act, may be permitted to directors, officers or persons controlling the registrant pursuant to the foregoing provisions, we have been informed that, in the opinion of the SEC such indemnification is against public policy as expressed in the Securities Act and is therefore unenforceable.

Transfer Agent and Registrar

The transfer agent and registrar for our common stock is American Stock Transfer & Trust Company, LLC. The telephone number of American Stock Transfer & Trust Company, LLC is (718) 921-8124.

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DESCRIPTION OF DEPOSITARY SHARES

We may offer depositary receipts representing fractional shares of our preferred stock, rather than full shares of preferred stock. The shares of preferred stock represented by depositary shares will be deposited under a depositary agreement between us and a bank or trust company that meets certain requirements and is selected by us (the "Bank Depositary"). Each owner of a depositary share will be entitled to all the rights and preferences of the preferred stock represented by the depositary share.

The description in an accompanying prospectus supplement of any depositary shares we offer will not necessarily be complete and will be qualified in its entirety by reference to the applicable depositary agreement, which will be filed with the SEC if we offer depositary shares. For more information on how you can obtain copies of any depositary agreement if we offer depositary shares, see "Where You Can Find More Information." We urge you to read the applicable depositary agreement and any accompanying prospectus supplement in their entirety.

Dividends and Other Distributions

If we pay a cash distribution or dividend on a series of preferred stock represented by depositary shares, the Bank Depositary will distribute such dividends to the record holders of such depositary shares. If the distributions are in property other than cash, the Bank Depositary will distribute the property to the record holders of the depositary shares. However, if the Bank Depositary determines that it is not feasible to make the distribution of property, the Bank Depositary may, with our approval, sell such property and distribute the net proceeds from such sale to the record holders of the depositary shares.

Redemption of Depositary Shares

If we redeem a series of preferred stock represented by depositary shares, the Bank Depositary will redeem the depositary shares from the proceeds received by the Bank Depositary in connection with the redemption. The redemption price per depositary share will equal the applicable fraction of the redemption price per share of the preferred stock. If fewer than all the depositary shares are redeemed, the depositary shares to be redeemed will be selected by lot or pro rata as the Bank Depositary may determine.

Voting the Preferred Stock

Upon receipt of notice of any meeting at which the holders of the preferred stock represented by depositary shares are entitled to vote, the Bank Depositary will mail the notice to the record holders of the depositary shares relating to such preferred stock. Each record holder of these depositary shares on the record date, which will be the same date as the record date for the preferred stock, may instruct the Bank Depositary as to how to vote the preferred stock represented by such holder's depositary shares. The Bank Depositary will endeavor, insofar as practicable, to vote the amount of the preferred stock represented by such depositary shares in accordance with such instructions, and we will take all action that the Bank Depositary deems necessary in order to enable the Bank Depositary to do so. The Bank Depositary will abstain from voting shares of the preferred stock to the extent it does not receive specific instructions from the holders of depositary shares representing such preferred stock.

Amendment and Termination of the Depositary Agreement

The form of depositary receipt evidencing the depositary shares and any provision of the depositary agreement may be amended by agreement between the Bank Depositary and us. However, any amendment that materially and adversely alters the rights of the holders of depositary shares will not be effective unless such amendment has been approved by the holders of at least a majority of the depositary shares then outstanding. The depositary agreement may be terminated by the Bank Depositary or us only if (1) all outstanding depositary

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shares have been redeemed or (2) there has been a final distribution in respect of the preferred stock in connection with any liquidation, dissolution or winding up of our company and such distribution has been distributed to the holders of depositary receipts.

Withdrawal of Preferred Stock

Except as may be provided otherwise in an accompanying prospectus supplement, upon surrender of depositary receipts at the principal office of the Bank Depositary, subject to the terms of the depositary agreement, the owner of the depositary shares may demand delivery of the number of whole shares of preferred stock and all money and other property, if any, represented by those depositary shares. Partial shares of preferred stock will not be issued. If the depositary receipts delivered by the holder evidence a number of depositary shares in excess of the number of depositary shares representing the number of whole shares of preferred stock to be withdrawn, the Bank Depositary will deliver to such holder at the same time a new depositary receipt evidencing the excess number of depositary shares. Holders of withdrawn preferred stock may not thereafter deposit those shares under the depositary agreement or receive depositary receipts evidencing depositary shares therefor.

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DESCRIPTION OF DEBT SECURITIES

We may offer secured or unsecured debt securities which may be senior, subordinated or junior subordinated, and which may be convertible. We may issue debt securities in one or more series.

The following description briefly sets forth certain general terms and provisions of the debt securities. The particular terms of the debt securities offered by any prospectus supplement and the extent, if any, to which these general provisions may apply to the debt securities, will be described in the applicable prospectus supplement. The form of indenture is filed as an exhibit to the registration statement of which this prospectus forms a part. The terms of the debt securities will include those set forth in the indenture, any related securities documents and those made a part of the indenture by the Trust Indenture Act of 1939, as amended (the "Trust Indenture Act"). You should read the summary below, the applicable prospectus supplement and the provisions of the indenture and any related security documents, if any, in their entirety before investing in our debt securities. Capitalized terms used in the summary have the meanings specified in the indenture.

The prospectus supplement relating to any series of debt securities that we may offer will contain the specific terms of the debt securities. These terms may include the following:

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General

We may sell the debt securities, including original issue discount securities, at par or at a substantial discount below their stated principal amount. Unless we inform you otherwise in a prospectus supplement, we may issue additional debt securities of a particular series without the consent of the holders of the debt securities of such series outstanding at the time of issuance. Any such additional debt securities, together with all other outstanding debt securities of that series, will constitute a single series of securities under the indenture. In addition, we will describe in the applicable prospectus supplement, material U.S. federal income tax considerations and any other special considerations for any debt securities we sell which are denominated in a currency or currency unit other than U.S. dollars. Unless we inform you otherwise in the applicable prospectus supplement, the debt securities will not be listed on any securities exchange.

United States federal income tax consequences and special considerations, if any, applicable to any such series will be described in an accompanying prospectus supplement.

We expect most debt securities to be issued in fully registered form without coupons and in denominations of $2,000 and any integral multiples thereof. Subject to the limitations provided in the indenture and in the applicable prospectus supplement, debt securities that are issued in registered form may be transferred or exchanged at the corporate office of the trustee or the principal corporate trust office of the trustee, without the payment of any service charge, other than any tax or other governmental charge payable in connection therewith.

Global Securities

Unless we inform you otherwise in the applicable prospectus supplement, the debt securities of a series may be issued in whole or in part in the form of one or more global securities that will be deposited with, or on behalf of, a depositary identified in the applicable prospectus supplement. Global securities will be issued in registered form and in either temporary or definitive form. Unless and until it is exchanged in whole or in part for the individual debt securities, a global security may not be transferred except as a whole by the depositary for such

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global security to a nominee of such depositary or by a nominee of such depositary to such depositary or another nominee of such depositary or by such depositary or any such nominee to a successor of such depositary or a nominee of such successor. The specific terms of the depositary arrangement with respect to any debt securities of a series and the rights of and limitations upon owners of beneficial interests in a global security will be described in the applicable prospectus supplement.

Governing Law

The indenture and the debt securities shall be construed in accordance with and governed by the laws of the State of New York.

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DESCRIPTION OF WARRANTS

We may issue warrants for the purchase of shares of our common stock, shares of preferred stock or our debt securities. We may issue warrants independently or together with other securities, and they may be attached to or separate from the other securities. Each series of warrants will be issued under a separate warrant agreement that we will enter into with a bank or trust company, as warrant agent, as detailed in an accompanying prospectus supplement. The warrant agent will act solely as our agent in connection with the warrants and will not assume any obligation, or agency or trust relationship, with you.

The prospectus supplement relating to a particular issue of warrants will describe the terms of those warrants, including, when applicable:

After warrants expire they will become void. The prospectus supplement may provide for the adjustment of the exercise price of the warrants.

Warrants may be exercised at the appropriate office of the warrant agent or any other office indicated in an accompanying prospectus supplement. Before the exercise of warrants, holders will not have any of the rights of holders of the securities purchasable upon exercise and will not be entitled to payments made to holders of those securities.

The description in an accompanying prospectus supplement of any warrants we offer will not necessarily be complete and will be qualified in its entirety by reference to the applicable warrant agreement, which will be filed with the SEC if we offer warrants. For more information on how you can obtain copies of any warrant agreement if we offer warrants, see "Where You Can Find More Information." We urge you to read the applicable warrant agreement and any accompanying prospectus supplement in their entirety.

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DESCRIPTION OF SUBSCRIPTION RIGHTS

We may issue subscription rights to purchase shares of our common stock, shares of our preferred stock or our debt securities. We may issue subscription rights independently or together with any other offered security, which may or may not be transferable by the stockholder. In connection with any offering of subscription rights, we may enter into a standby arrangement with one or more underwriters or other purchasers pursuant to which the underwriters or other purchasers may be required to purchase any securities remaining unsubscribed for after such offering.

The prospectus supplement relating to any subscription rights we may offer will contain the specific terms of the subscription rights. These terms may include the following:

The description in an accompanying prospectus supplement of any subscription rights we offer will not necessarily be complete and will be qualified in its entirety by reference to the applicable subscription rights certificate or subscription rights agreement, which will be filed with the SEC if we offer subscription rights. For more information on how you can obtain copies of any subscription rights certificate or subscription rights agreement if we offer subscription rights, see "Where You Can Find More Information." We urge you to read the applicable subscription rights certificate, the applicable subscription rights agreement and any accompanying prospectus supplement in their entirety.

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DESCRIPTION OF PURCHASE CONTRACTS

We may issue, from time to time, purchase contracts, including contracts entitling and/or obligating holders to purchase from us and requiring us to sell to the holders, a specified principal amount of debt securities, shares of common stock or preferred stock, depositary shares, government securities, or other securities that we may sell under this prospectus at a future date or dates. The consideration payable upon settlement of the purchase contracts may be fixed at the time the purchase contracts are issued or may be determined by a specific reference to a formula set forth in the purchase contracts. The purchase contracts may be issued separately or as part of units consisting of a purchase contract and other securities or obligations issued by us or third parties, including United States treasury securities, securing the holders' obligations to purchase the relevant securities under the purchase contracts. The purchase contracts may require us to make periodic payments to the holders of the purchase contracts or units or vice versa, and the payments may be unsecured or prefunded on some basis. The purchase contracts may require holders to secure their obligations under the purchase contracts and, in certain circumstances, we may deliver a newly issued prepaid purchase contract, which is referred to as a "prepaid security," upon release to a holder of any collateral securing such holder's obligations under the original contract.

The prospectus supplement related to any particular purchase contracts and, if applicable, prepaid security, will describe, among other things, the material terms of the purchase contracts and of the securities being sold pursuant to such purchase contracts, and, if applicable, the prepaid securities and the documents pursuant to which such prepaid securities will be issued, a discussion, if appropriate, of any special United States federal income tax considerations applicable to the purchase contracts and any material provisions governing the purchase contracts that differ from those described above.

The description in an accompanying prospectus supplement of any purchase contract we offer will not necessarily be complete and will be qualified in its entirety by reference to the purchase contracts and, if applicable, collateral arrangements and depositary arrangements, relating to the purchase contracts. Alternatively, purchase contracts may require holders to satisfy their obligations thereunder when the purchase contracts are issued. For more information on how you can obtain copies of any purchase contract we may offer, see "Where You Can Find More Information." We urge you to read the applicable purchase contract and any accompanying prospectus supplement in their entirety.

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DESCRIPTION OF PURCHASE UNITS

We may, from time to time, issue units comprised of one or more of certain other securities that may be offered under this prospectus, in any combination. Each unit may also include debt obligations of third parties, such as U.S. Treasury securities. Each unit will be issued so that the holder of the unit is also the holder of each security included in the unit. Thus, the holder of a unit will have the rights and obligations of a holder of each included security. The unit agreement under which a unit is issued may provide that the securities included in the unit may not be held or transferred separately at any time, or at any time before a specified date.

Any prospectus supplement related to any particular units will describe, among other things:

The description in an accompanying prospectus supplement of any purchase unit we offer will not necessarily be complete and will be qualified in its entirety by reference to the purchase units and, if applicable, collateral arrangements and depositary arrangements, relating to the purchase units. Alternatively, purchase units may require holders to satisfy their obligations thereunder when the purchase units are issued. For more information on how you can obtain copies of any purchase unit we may offer, see "Where You Can Find More Information." We urge you to read the applicable purchase unit and any accompanying prospectus supplement in their entirety.

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SELLING SECURITYHOLDERS

Information about selling securityholders, where applicable, will be set forth in a prospectus supplement, in a post-effective amendment or in filings we make with the SEC under the Exchange Act which are incorporated by reference into this prospectus.

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PLAN OF DISTRIBUTION

We or the selling securityholders may sell the applicable securities offered by this prospectus from time to time in one or more transactions, including without limitation:

A distribution of the securities offered by this prospectus may also be effected through the issuance of derivative securities, including without limitation, warrants, subscriptions, exchangeable securities, forward delivery contracts and the writing of options.

In addition, the manner in which we or the selling securityholders may sell some or all of the securities covered by this prospectus, include, without limitation, through:

We or the selling securityholders may also enter into hedging transactions. For example, we or the selling securityholders may:

In addition, we or the selling securityholders may enter into derivative or hedging transactions with third parties, or sell securities not covered by this prospectus to third parties in privately negotiated transactions. In connection with such a transaction, the third parties may sell the applicable securities covered by and pursuant to this prospectus and an applicable prospectus supplement or pricing supplement, as the case may be. If so, the

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third party may use securities borrowed from us, the selling securityholders or others to settle such sales and may use securities received from us or the selling securityholders to close out any related short positions. We or the selling securityholders may also loan or pledge securities covered by this prospectus and an applicable prospectus supplement to third parties, who may sell the loaned securities or, in an event of default in the case of a pledge, sell the pledged securities pursuant to this prospectus and the applicable prospectus supplement or pricing supplement, as the case may be.

A prospectus supplement with respect to each offering of securities will state the terms of the offering of the securities, including:

The offer and sale of the securities described in this prospectus by us, the selling securityholders, the underwriters or the third parties described above may be effected from time to time in one or more transactions, including privately negotiated transactions, either:

General

Any public offering price and any discounts, commissions, concessions or other items constituting compensation allowed or reallowed or paid to underwriters, dealers, agents or remarketing firms may be changed from time to time. Any underwriters, dealers, agents and remarketing firms that participate in the distribution of the offered securities may be "underwriters" as defined in the Securities Act. Any discounts or commissions they receive from us or the selling securityholders and any profits they receive on the resale of the offered securities may be treated as underwriting discounts and commissions under the Securities Act. We will identify any underwriters, agents or dealers and describe their commissions, fees or discounts in the applicable prospectus supplement or pricing supplement, as the case may be.

Underwriters and Agents

If underwriters are used in a sale, they will acquire the offered securities for their own account. The underwriters may resell the offered securities in one or more transactions, including negotiated transactions. These sales may be made at a fixed public offering price or prices, which may be changed, at market prices prevailing at the time of the sale, at prices related to such prevailing market price or at negotiated prices. We or the selling securityholders may offer the securities to the public through an underwriting syndicate or through a single underwriter. The underwriters in any particular offering will be mentioned in the applicable prospectus supplement or pricing supplement, as the case may be.

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Unless otherwise specified in connection with any particular offering of securities, the obligations of the underwriters to purchase the offered securities will be subject to certain conditions contained in an underwriting agreement that we or the selling securityholders will enter into with the underwriters at the time of the sale to them. The underwriters will be obligated to purchase all of the securities of the series offered if any of the securities are purchased, unless otherwise specified in connection with any particular offering of securities. Any initial offering price and any discounts or concessions allowed, reallowed or paid to dealers may be changed from time to time.

We or the selling securityholders may designate agents to sell the offered securities. Unless otherwise specified in connection with any particular offering of securities, the agents will agree to use their best efforts to solicit purchases for the period of their appointment. We or the selling securityholders may also sell the offered securities to one or more remarketing firms, acting as principals for their own accounts or as agents for us or the selling securityholders. These firms will remarket the offered securities upon purchasing them in accordance with a redemption or repayment pursuant to the terms of the offered securities. A prospectus supplement or pricing supplement, as the case may be will identify any remarketing firm and will describe the terms of its agreement, if any, with us and its compensation.

In connection with offerings made through underwriters or agents, we or the selling securityholders may enter into agreements with such underwriters or agents pursuant to which we or the selling securityholders receive our outstanding securities in consideration for the securities being offered to the public for cash. In connection with these arrangements, the underwriters or agents may also sell securities covered by this prospectus to hedge their positions in these outstanding securities, including in short sale transactions. If so, the underwriters or agents may use the securities received from us or the selling securityholders under these arrangements to close out any related open borrowings of securities.

Dealers

We or the selling securityholders may sell the offered securities to dealers as principals. We or the selling securityholders may negotiate and pay dealers' commissions, discounts or concessions for their services. The dealer may then resell such securities to the public either at varying prices to be determined by the dealer or at a fixed offering price agreed to with us or the selling securityholders at the time of resale. Dealers engaged by us or the selling securityholders may allow other dealers to participate in resales.

Direct Sales

We or the selling securityholders may choose to sell the offered securities directly. In this case, no underwriters or agents would be involved.

At-the-Market Offerings

We or the selling securityholders may also sell the securities offered by any applicable prospectus supplement in "at-the-market offerings" within the meaning of Rule 415 of the Securities Act, to or through a market maker or into an existing trading market, on an exchange or otherwise.

Institutional Purchasers

We or the selling securityholders may authorize agents, dealers or underwriters to solicit certain institutional investors to purchase offered securities on a delayed delivery basis pursuant to delayed delivery contracts providing for payment and delivery on a specified future date. The applicable prospectus supplement or pricing supplement, as the case may be, will provide the details of any such arrangement, including the offering price and commissions payable on the solicitations.

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We or the selling securityholders will enter into such delayed contracts only with institutional purchasers that we approve. These institutions may include commercial and savings banks, insurance companies, pension funds, investment companies and educational and charitable institutions.

Indemnification; Other Relationships

We or the selling securityholders may have agreements with agents, underwriters, dealers and remarketing firms to indemnify them against certain civil liabilities, including liabilities under the Securities Act. Agents, underwriters, dealers and remarketing firms, and their affiliates, may engage in transactions with, or perform services for, us or the selling securityholders in the ordinary course of business. This includes commercial banking and investment banking transactions.

Market-Making, Stabilization and Other Transactions

There is currently no market for any of the offered securities, other than the common stock which is listed on the NYSE. If the offered securities are traded after their initial issuance, they may trade at a discount from their initial offering price, depending upon prevailing interest rates, the market for similar securities and other factors. While it is possible that an underwriter could inform us that it intends to make a market in the offered securities, such underwriter would not be obligated to do so, and any such market-making could be discontinued at any time without notice. Therefore, no assurance can be given as to whether an active trading market will develop for the offered securities. We have no current plans for listing of the preferred stock or debt securities on any securities exchange or quotation system; any such listing with respect to any preferred stock or any debt securities will be described in the applicable prospectus supplement or pricing supplement, as the case may be.

In connection with any offering of common stock, preferred stock, debt securities or securities that provide for the issuance of shares of our common stock upon conversion, exchange or exercise, as the case may be, the underwriters may purchase and sell shares of common stock, preferred stock or our debt securities in the open market. These transactions may include short sales, syndicate covering transactions and stabilizing transactions. Short sales involve syndicate sales of common stock in excess of the number of shares to be purchased by the underwriters in the offering, which creates a syndicate short position. "Covered" short sales are sales of shares made in an amount up to the number of shares represented by the underwriters' over-allotment option. In determining the source of shares to close out the covered syndicate short position, the underwriters will consider, among other things, the price of shares available for purchase in the open market as compared to the price at which they may purchase shares through the over-allotment option. Transactions to close out the covered syndicate short involve either purchases of the common stock in the open market after the distribution has been completed or the exercise of the over-allotment option. The underwriters may also make "naked" short sales of shares in excess of the over-allotment option. The underwriters must close out any naked short position by purchasing shares of common stock in the open market. A naked short position is more likely to be created if the underwriters are concerned that there may be downward pressure on the price of the shares in the open market after pricing that could adversely affect investors who purchase in the offering. Stabilizing transactions consist of bids for or purchases of shares in the open market while the offering is in progress for the purpose of pegging, fixing or maintaining the price of the securities.

In connection with any offering, the underwriters may also engage in penalty bids. Penalty bids permit the underwriters to reclaim a selling concession from a syndicate member when the securities originally sold by the syndicate member are purchased in a syndicate covering transaction to cover syndicate short positions. Stabilizing transactions, syndicate covering transactions and penalty bids may cause the price of the securities to be higher than it would be in the absence of the transactions. The underwriters may, if they commence these transactions, discontinue them at any time.

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LEGAL MATTERS

Unless otherwise indicated in any accompanying prospectus supplement, Skadden, Arps, Slate, Meagher & Flom LLP, New York, New York, will provide opinions regarding the authorization and validity of the securities. Skadden, Arps, Slate, Meagher & Flom LLP may also provide opinions regarding certain other matters. Any underwriters will be advised about legal matters by their own counsel, which will be named in an accompanying prospectus supplement.

EXPERTS

The consolidated financial statements of Brookdale Senior Living Inc. appearing in Brookdale Senior Living Inc.'s Annual Report (Form 10-K) for the year ended December 31, 2021 (including the schedule appearing therein) and the effectiveness of Brookdale Senior Living Inc.'s internal control over financial reporting as of December 31, 2021 have been audited by Ernst & Young LLP, independent registered public accounting firm, as set forth in their reports thereon, included therein, and incorporated herein by reference. Such consolidated financial statements are incorporated herein by reference in reliance upon such reports given on the authority of such firm as experts in accounting and auditing.

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Brookdale Senior Living Inc.

Up to 54,968,244 Shares of common stock

Prospectus Supplement

October 23, 2024