花旗集团美股招股说明书(2026-04-06版)

pricing supplement and the accompanying product supplement, underlying supplement, prospectus supplementand prospectus are not an offer to sell these securities, nor are they soliciting an offer to buy these securities, inany state where the offer or sale is not permitted.Subject to Completion. Dated April 6, 2026 Filed Pursuant to Rule 424(b)(2) Registration Statement Nos. 333-293732 and 333-293732-02Citigroup Global Markets Holdings Inc.$Buffered S&P 500®Index-Linked Notes dueAll Payments Due from Citigroup Global Markets Holdings Inc.Fully and Unconditionally Guaranteed by Citigroup Inc.Unlike conventional debt securities, the notes offered by this pricing supplement do not pay interest and do not repay a fixed amount of principal at maturity.The amount that you will be paid on your notes on the maturity date(expected to be the second business day after the scheduled determination date) is based on the performance of the S&P500®Index (the “underlier”) as measured from the trade date to and including the determination date (expected to bebetween 15 and 17 months after the trade date).If the final underlier level on the determination date is greater than theinitial underlier level (set on the trade date and may be higher or lower than the actual closing level of the underlier on thetrade date), the return on your notes will be positive, subject to the maximum settlement amount (set on the trade date andexpected to be between $1,155.04 and $1,182.24 for each $1,000 stated principal amount of your notes).If the finalunderlier level declines from the initial underlier level by up to a buffer amount of 12.50%, you will receive the statedprincipal amount of your notes.However, if the final underlier level declines from the initial underlier level by morethan the 12.50% buffer amount, the return on your notes will be negative and you will lose approximately 1.1429%of the stated principal amount of your notes for every 1% by which that decline exceeds the 12.50% bufferamount. You could lose your entire investment in the notes.In exchange for the upside participation and limited bufferfeatures of the notes, you must be willing to forgo (i) any return in excess of the maximum return at maturity of 15.504% to18.224% (set on the trade date and results from the maximum settlement amount), (ii) any dividends paid on the stocksincluded in the underlier and (iii) interest on the notes.To determine your payment at maturity, we will calculate the underlier return, which is the percentage increase or decrease in the level of the underlier from the initial underlier level (set on the trade date) to the final underlier level on thedetermination date. On the maturity date, for each $1,000 stated principal amount note you then hold, you will receive anamount in cash equal to:if the underlier return ispositive(the final underlier level isgreater thanthe initial underlier level), thesumof (i) $1,000plus(ii) theproductof (a) $1,000times(b) the upside participation rate of 170%times(c) the underlierreturn, subject to the maximum settlement amount;if the underlier return iszeroornegativebutnot below-12.50% (the final underlier level isequal toorless thantheinitial underlier level but not by more than 12.50%), $1,000; orif the underlier return isnegativeand isbelow-12.50% (the final underlier level isless thanthe initial underlierlevel by more than 12.50%), thesumof (i) $1,000plus(ii) theproductof (a) approximately 1.1429times(b) thesumof the underlier returnplus12.50%times(c) $1,000.This amount will be less than $1,000 and may bezero.The notes are unsecured senior debt securities issued by Citigroup Global Markets Holdings Inc. and guaranteed by Citigroup Inc.All payments on the notes are subject to the credit risk of Citigroup Global Markets Holdings Inc. andCitigroup Inc.If Citigroup Global Markets Holdings Inc. and Citigroup Inc. default on their obligations, you may not receiveany amount due under the notes.The notes will not be listed on any securities exchange and may have limited or noliquidity.Investing in the notes involves risks not associated with an investment in conventional debt securities. See “Summary Risk Factors” beginning on page PS-7.(1)(2) (1) Citigroup Global Markets Holdings Inc. currently expects that the estimated value of the notes on the trade date will bebetween $977.50 and $997.50 per note, which will be less than the issue price.The estimated value of the notes is basedon proprietary pricing models of Citigroup Global Markets Inc. (“CGMI”) and our internal funding rate. It is not an indicationof actual profit to CGMI or other of our affiliates, nor is it an indication of the price, if any, at which CGMI or any otherperson may be willing to buy the notes from you at any time after issuance.See “Valuation of the Notes” in this pricingsupplement.(2) CGMI, an affiliate of the issuer, is the underwriter for the offering of the notes and is acting as principal. For more information on the distribu