Citizens Financial : Prospectus filed pursuant to Rule 424(b)(2)

Table of Contents

Filed Pursuant to Rule 424(b)(2)

Registration No.: 333-227792

The information in this preliminary prospectus supplement is not complete and may be changed. This preliminary prospectus supplement and the accompanying prospectus are not an offer to sell nor do they seek an offer to buy these securities in any jurisdiction where the offer or sale is not permitted.

PRELIMINARY PROSPECTUS SUPPLEMENT (Subject to Completion) (To Prospectus dated October 11, 2018)

Issued October 21, 2019

Depositary Shares Each Representing a 1/40th Interest in a Share of

% Fixed-RateNon-Cumulative Perpetual Preferred Stock, Series E

Citizens Financial Group, Inc. ("Citizens") is offering

depositary shares (the "Depositary Shares"), each of which represents a 1/40th ownership interest in a share of Citizens'

• Fixed-RateNon-Cumulative Perpetual Preferred Stock, Series E, liquidation preference $1,000 per share ("Series E Preferred Stock") (equivalent to $25 per Depositary Share), deposited with Computershare Inc. and Computershare Trust Company, N.A., acting jointly as depositary. The Depositary Shares are evidenced by depositary receipts. Each holder of a Depositary Share will be entitled, through the depositary, to all the rights and preferences of the shares of Series E Preferred Stock represented thereby (including dividend, voting, redemption and liquidation rights) in proportion to the applicable fraction of a share of Series E Preferred Stock represented by such Depositary Share.

Holders of Series E Preferred Stock will be entitled to receive dividend payments only when, as and if declared by our board of directors (or a duly authorized committee of the board). Any such dividends will be payable quarterly in arrears on January 6, April 6, July 6 and October 6 of each year, beginning on January 6, 2020. From the date of original issue, dividends will be payable at a rate of % per annum.

Dividends on the Series E Preferred Stock will be non-cumulative. In the event dividends are not declared on Series E Preferred Stock for payment on any dividend payment date, then those dividends will not be cumulative and will not accrue or be payable, and if we have not declared a dividend before the dividend payment date for any dividend period, we will have no obligation to pay dividends for that dividend period, whether or not dividends on the Series E Preferred Stock are declared for any future dividend period.

We may, at our option, redeem the Series E Preferred Stock (i) in whole or in part, from time to time, on any dividend payment date on or after January 6, 2025, or (ii) in whole but not in part, at any time within 90 days following a Regulatory Capital Treatment Event (as defined herein), in each case at a redemption price of $1,000 per share (equivalent to $25 per Depositary Share), plus any declared and unpaid dividends to, but excluding, the date fixed for redemption, without accumulation of any undeclared dividends. If we redeem the Series E Preferred Stock, the depositary will redeem a proportionate number of Depositary Shares. The Series E Preferred Stock will not have voting rights, except as set forth under "Description of the Series E Preferred Stock-Voting Rights" beginning on page S-22.

Application will be made to list the Depositary Shares on the New York Stock Exchange under the symbol "CFG PrE." If approved for listing, trading of the Depositary Shares on the New York Stock Exchange is expected to commence within a 30-day period after the initial delivery of the Depositary Shares.

Neither the Series E Preferred Stock nor the Depositary Shares are savings accounts, deposits or other obligations of any of our bank or non-bank subsidiaries, and they are not insured by the Federal Deposit Insurance Corporation or any other governmental agency or instrumentality.

Investing in the Depositary Shares involves risk. See "Risk Factors" beginning on page S-8 of this prospectus supplement and on page 22 of our Annual Report on Form 10-K for the year ended December 31, 2018 to read about factors you should consider before making a decision to invest in the Depositary Shares.

Neither the Securities and Exchange Commission, any state securities commission, the Federal Deposit Insurance Corporation, the Board of Governors of the Federal Reserve System nor any other regulatory body has approved or disapproved of these securities or determined if this prospectus supplement or the accompanying prospectus is truthful or complete. Any representation to the contrary is a criminal offense.

			Per			Total
			Share
Initial Public Offering Price(1)		$			$
Underwriting Discount(2)		$			$
Proceeds, Before Expenses, to Citizens Financial Group, Inc.		$			$

1. The initial public offering price set forth above does not include dividends, if any, that may be declared. Dividends, if declared, will be calculated from the date of original

	issuance, which is expected to be October , 2019.
(2)	Reflects	Depositary Shares sold to institutional investors, for which the underwriters receive an underwriting discount of $	per Depositary Share, and
	Depositary Shares sold to retail investors, for which the underwriters receive an underwriting discount of $	per Depositary Share, assuming no exercise of the
	underwriters' over-allotment option described below.
We have granted the underwriters the option to purchase up to an additional	Depositary Shares from us within 30 days after the date of this prospectus supplement at the public

offering price, less the applicable underwriting discounts and commissions, solely to cover over-allotments, if any.

The underwriters expect to deliver the Depositary Shares in book-entry form only through the facilities of The Depository Trust Company against payment in New York, New York on October , 2019. Beneficial interests in the Depositary Shares will be shown on, and transfers thereof will be effected only through, records maintained by The Depository Trust Company and its direct and indirect participants, including Clearstream Banking, société anonyme, Luxembourg and Euroclear Bank S.A./N.V.

	Joint Book-Running Managers
Morgan Stanley	BofA Securities	J.P. Morgan
UBS Investment Bank	Wells Fargo Securities	Citizens Capital Markets

Prospectus Supplement dated October , 2019

Table of Contents

TABLE OF CONTENTS

Prospectus Supplement

ABOUT THIS PROSPECTUS SUPPLEMENT	Page
S-ii
WHERE YOU CAN FIND MORE INFORMATION	S-iii
CAUTIONARY NOTE REGARDING FORWARD-LOOKING STATEMENTS	S-iv
SUMMARY	S-1
RISK FACTORS	S-8
USE OF PROCEEDS	S-13
CAPITALIZATION	S-14
CAPITAL COMPONENTS AND RATIOS	S-16
DESCRIPTION OF THE SERIES E PREFERRED STOCK	S-17
DESCRIPTION OF THE DEPOSITARY SHARES	S-28
BOOK-ENTRY, DELIVERY AND FORM OF DEPOSITARY SHARES	S-31
MATERIAL U.S. FEDERAL INCOME TAX CONSIDERATIONS	S-35
EMPLOYEE RETIREMENT INCOME SECURITY ACT	S-40
UNDERWRITING (CONFLICTS OF INTEREST)	S-42
VALIDITY OF SHARES	S-48
EXPERTS	S-48
Prospectus
CITIZENS FINANCIAL GROUP, INC.	Page
1
ABOUT THIS PROSPECTUS	2
WHERE YOU CAN FIND MORE INFORMATION	3
SPECIAL NOTE ON FORWARD-LOOKING STATEMENTS	4
RISK FACTORS	5
USE OF PROCEEDS	6
RATIOS OF EARNINGS TO FIXED CHARGES AND EARNINGS TO FIXED CHARGES AND PREFERRED DIVIDENDS	7
DESCRIPTION OF CAPITAL STOCK	8
DESCRIPTION OF DEPOSITARY SHARES	12
DESCRIPTION OF DEBT SECURITIES	12
DESCRIPTION OF WARRANTS	13
DESCRIPTION OF PURCHASE CONTRACTS	13
DESCRIPTION OF UNITS	14
PLAN OF DISTRIBUTION (CONFLICTS OF INTEREST)	15
VALIDITY OF SECURITIES	17
EXPERTS	17
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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. The second part is the prospectus, which describes more general information, some of which may not apply to this offering. You should read both this prospectus supplement and the accompanying prospectus, together with additional information described below under the heading "Where You Can Find More Information."

Unless otherwise mentioned or unless the context requires otherwise (for example, in references under "Cautionary Note Regarding Forward-Looking Statements," "Summary-Citizens Financial Group, Inc.," "Capitalization" and "Capital Components and Ratios"), all references in this prospectus supplement to "Citizens," the "Company," "we," "us," "our" or similar references mean Citizens Financial Group, Inc. and do not include its subsidiaries.

If the information set forth in this prospectus supplement differs in any way from the information set forth in the accompanying prospectus, you should rely on the information set forth in this prospectus supplement.

Neither we nor the underwriters have authorized anyone to provide you with information other than the information contained in this prospectus supplement and the accompanying prospectus, including the information incorporated by reference, or any free writing prospectus that we prepare and distribute. Neither we nor the underwriters take any responsibility for, or provide any assurance as to the reliability of, any other information that others may give you. This prospectus supplement, the accompanying prospectus and any such free writing prospectus may be used only for the purposes for which they have been prepared.

We are not, and the underwriters are 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 appearing in this prospectus supplement or any document incorporated by reference is accurate as of any date other than the date of the applicable document. Our business, financial condition, results of operations and prospects may have changed since that date. Neither this prospectus supplement nor the accompanying prospectus constitutes an offer, or an invitation on our behalf or on behalf of the underwriters, to subscribe for and purchase, any of the securities and may not be used for or in connection with an offer or solicitation by anyone, in any jurisdiction in which such an offer or solicitation is not authorized or to any person to whom it is unlawful to make such an offer or solicitation.

PRIIPs Regulation / Prohibition of Sales to EEA Retail Investors

The Depositary Shares are not intended to be offered, sold or otherwise made available to and should not be offered, sold or otherwise made available to any retail investor in the European Economic Area ("EEA"). For these purposes, a retail investor means a person who is one (or more) of: (i) a retail client as defined in point (11) of Article 4(1) of Directive 2014/65/EU (as amended, "MiFID II"); (ii) a customer within the meaning of Directive (EU) 2016/97 (the "Insurance Distribution Directive"), where that customer would not qualify as a professional client as defined in point (10) of Article 4(1) of MiFID II; or (iii) not a qualified investor as defined in Regulation (EU) 2017/1129 (the "Prospectus Regulation"). Consequently, no key information document required by Regulation (EU) No 1286/2014 (as amended, the "PRIIPs Regulation") for offering or selling the shares or otherwise making them available to retail investors in the EEA has been prepared and therefore offering or selling the shares or otherwise making them available to any retail investor in the EEA may be unlawful under the PRIIPs Regulation.

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WHERE YOU CAN FIND MORE INFORMATION

We file annual, quarterly and current reports, proxy statements and other information with the Securities and Exchange Commission, or the "SEC." Our SEC filings are available to the public from the SEC's web site at http://www.sec.gov. Our SEC filings are also available at the offices of the New York Stock Exchange, or the "NYSE." For further information on obtaining copies of our public filings at the NYSE, you should call 212-656-3000.

The SEC allows us to incorporate by reference the information we file with them, which means that we can disclose important information to you by referring you to those documents. The information incorporated by reference is considered to be a part of this prospectus supplement, and later information that we file with the SEC will automatically update and supersede this information. We incorporate by reference the following documents listed below and any future filings made with the SEC under Section 13(a), 13(c), 14 or 15(d) of the Securities Exchange Act of 1934, as amended, or the "Exchange Act," prior to the termination of the offering (other than, in each case, information that is deemed not to have been filed in accordance with SEC rules):

• Annual Report on Form 10-Kfor the year ended December 31, 2018, filed on February 21, 2019, including information specifically incorporated therein by reference from our definitive proxy statementon Schedule 14A for the 2019 Annual Meeting of Shareholders, filed on March 8, 2019;
• Quarterly Reports on Form 10-Q for the quarters ended March 31, 2019 and June 30, 2019, filed on May 8, 2019and August 6, 2019, respectively; and
• Current Reports on Form 8-Kfiled on January 22, 2019, January 29, 2019, April 26, 2019, June 21, 2019, July 22, 2019, July 25, 2019and October 21, 2019.

You may request a copy of these filings (other than an exhibit to a filing unless that exhibit is specifically incorporated by reference into that filing), at no cost, by writing or calling us at the following address:

Citizens Financial Group, Inc.

600 Washington Blvd.

Stamford, CT 06901

Attn: Corporate Secretary

Telephone: [phone]

E-mail: [e-mail]

We have also filed a registration statement (No. 333-227792) with the SEC relating to the securities offered by this prospectus supplement and the accompanying prospectus. This prospectus supplement is part of the registration statement. You may obtain from the SEC a copy of the registration statement and exhibits that we filed with the SEC when we registered the Depositary Shares and the Series E Preferred Stock. The registration statement may contain additional information that may be important to you.

Our reports and documents incorporated by reference into this prospectus supplement may also be found in the "Investor Relations" section of our website at http://www.citizensbank.com. Our website and the information contained in it or connected to it shall not be deemed to be incorporated into this prospectus supplement or any registration statement of which it forms a part.

Unless otherwise indicated, currency amounts in this prospectus supplement are stated in U.S. dollars.

S-iii

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CAUTIONARY NOTE REGARDING FORWARD-LOOKING STATEMENTS

The information included or incorporated by reference in this prospectus supplement may contain forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995. Any statement that does not describe historical or current facts is a forward-looking statement. These statements often include the words "believes," "expects," "anticipates," "estimates," "intends," "plans," "goals," "targets," "initiatives," "potentially," "probably," "projects," "outlook" or similar expressions or future conditional verbs such as "may," "will," "should," "would," and "could."

Forward-looking statements are based upon the current beliefs and expectations of management, and on information currently available to management. Our statements speak as of the date hereof, and we do not assume any obligation to update the statements included or incorporated by reference herein or to update the reasons why actual results could differ from those contained in such statements in light of new information or future events. We caution you, therefore, against relying on any of these forward-looking statements. They are neither statements of historical fact nor guarantees or assurances of future performance. While there is no assurance that any list of risks and uncertainties or risk factors is complete, important factors that could cause actual results to differ materially from those in the forward-looking statements include the following, without limitation:

• Negative economic and political conditions that adversely affect the general economy, housing prices, the job market, consumer confidence and spending habits which may affect, among other things, the level of nonperforming assets, charge-offs and provision expense;
• The rate of growth in the economy and employment levels, as well as general business and economic conditions, and changes in the competitive environment;
• Our ability to implement our business strategy, including the cost savings and efficiency components, and achieve our financial performance goals;
• Our ability to meet heightened supervisory requirements and expectations;
• Liabilities and business restrictions resulting from litigation and regulatory investigations;
• Our capital and liquidity requirements (including under regulatory capital standards, such as the U.S. Basel III capital rules) and our ability to generate capital internally or raise capital on favorable terms;
• The effect of changes in interest rates on our net interest income, net interest margin and our mortgage originations, mortgage servicing rights and mortgages held for sale;
• Changes in interest rates and market liquidity, as well as the magnitude of such changes, which may reduce interest margins, impact funding sources and affect the ability to originate and distribute financial products in the primary and secondary markets;
• The effect of changes in the level of checking or savings account deposits on our funding costs and net interest margin;
• Financial services reform and other current, pending or future legislation or regulation that could have a negative effect on our revenue and businesses, including the Dodd-Frank Act and other legislation and regulation relating to bank products and services;
• A failure in or breach of our operational or security systems or infrastructure, or those of our third party vendors or other service providers, including as a result of cyber-attacks; and
• Management's ability to identify and manage these and other risks.

More information about factors that could cause actual results to differ materially from those described in the forward-looking statements can be found in the risk factors included in our Annual Report on Form 10-K for the year ended December 31, 2018, as well as the other information included or incorporated by reference in this prospectus supplement and the accompanying prospectus.

S-iv