花旗集团美股招股说明书(2026-03-05版)

The information in this preliminary pricing supplement is not complete and may be changed. This preliminary pricing supplement, theaccompanying product supplement, underlying supplement, prospectus supplement and prospectus are not an offer to sell these securities, nor arethey soliciting an offer to buy these securities, in any state where the offer or sale is not permitted. March----, 2026Medium-Term Senior Notes, Series NPricing Supplement No. 2026-USNCH30591 to Product Supplement No. EA-08-03dated February 25, 2026, Underlying Supplement No. 13 dated February 25, 2026 andProspectus Supplement and Prospectus each dated February 25, 2026Citigroup Global Markets Holdings Inc. All Payments Due from Citigroup Global Markets Holdings Inc. Fully and Unconditionally Guaranteed by Citigroup Inc.Market Linked Securities—Contingent Fixed Return and Contingent Downside Principal at Risk Securities Linked to the Lowest Performing of the Dow Jones Industrial Average™ and the Russell 2000®Index due April 3, 2031 Linked to the lowest performing of the Dow Jones Industrial Average(each referred to as an “underlying”) Unlike ordinary debt securities, the securities do not pay interest or repay a fixed amount of principal at maturity.Instead, thesecurities provide for a maturity payment amount that may be greater than, equal to or less than the stated principal amount ofthe securities, depending on the performance of the lowest performing underlying from its starting value to its ending value.Thematurity payment amount will reflect the following terms: that is greater than or equal to its threshold value, you will receive the stated principal amountplusthe contingent fixed return of at least 52.25% (to be determined on the pricing date) of the stated principal amountIf the value of the lowest performing underlying decreases but the decrease is to a value that is less than its threshold valuebut greater than or equal to its downside threshold value, you will be repaid the stated principal amountIf the value of the lowest performing underlying decreases to a value less than its downside threshold value, you will lose asignificant portion, and possibly all, of the stated principal amount of your securitiesThe lowest performing underlying is the underlying that has the lowest underlying returnThe threshold value for each underlying is equal to 90% of its starting valueThe downside threshold value for each underlying is equal to 70% of its starting valueInvestors may lose up to 100% of the stated principal amountAny positive return on the securities at maturity will be limited to the contingent fixed return, even if the ending value of thelowest performing underlying significantly exceeds its starting value; you will not participate in any appreciation of the lowestperforming underlying beyond the contingent fixed return Your return on the securities will depend solely on the performance of the underlying that is the lowest performing underlying.You will not benefit in any way from the performance of any better performing underlying. Therefore, you will be adverselyaffected if any underlying performs poorly, even if any other underlying performs favorably. All payments on the securities are subject to the credit risk of Citigroup Global Markets Holdings Inc. and Citigroup Inc.; ifCitigroup Global Markets Holdings Inc. and Citigroup Inc. default on their obligations, you could lose some or all of yourinvestment The securities will not be listed on any securities exchange and, accordingly, may have limited or no liquidity. You should notinvest in the securities unless you are willing to hold them to maturity.The securities have complex features and investing in the securities involves risks not associated with an investment in conventional debt securities. See “Summary Risk Factors” beginning on pagePS-7 and “Risk Factors” beginning on page PS-5 of the accompanying product supplement and Neither the Securities and Exchange Commission (the “SEC”) nor any state securities commission has approved ordisapproved of the securities or determined that this pricing supplement or the accompanying product supplement,underlying supplement, prospectus supplement and prospectus are truthful or complete. Any representation to the The securities are unsecured debt obligations issued by Citigroup Global Markets Holdings Inc. and guaranteed byCitigroup Inc.All payments due on the securities are subject to the credit risk of Citigroup Global Markets Holdings Inc.and Citigroup Inc.None of Wells Fargo Securities, LLC (“Wells Fargo”) or any of its affiliates will have any liability to thepurchasers of the securities in the event Citigroup Global Markets Holdings Inc. defaults on its obligations under thesecurities and Citigroup Inc. defaults on its guarantee obligations.The securities are not bank deposits and are not (1) Citigroup Global Markets Holdings Inc. currently expects that the estimated value of the securities on