花旗集团美股招股说明书(2026-04-02版)

The information in this preliminary pricing supplement is not complete and may be changed. A registration statement relating to these securities has been filed with the Securities andExchange Commission. This preliminary pricing supplement and the accompanying product supplement, underlying supplement, prospectus supplement and prospectus are not an offerto sell these securities, nor are they soliciting an offer to buy these securities, in any state where the offer or sale is not permitted.SUBJECT TO COMPLETION, DATED APRIL 2, 2026 April, 2026Medium-Term Senior Notes, Series NPricing Supplement No. 2026-USNCH31390Filed Pursuant to Rule 424(b)(2)Registration Statement Nos. 333-293732 and 333-293732-02 Citigroup Global Markets Holdings Market-Linked Securities Linked to the Worst Performing of the Russell 2000®Index and the S&P 500®Index Due April 14, 2027 ▪The securities offered by this pricing supplement are unsecured debt securities issued by Citigroup Global Markets Holdings Inc. and guaranteed by Citigroup Inc. Unlike conventional debtsecurities, the securities do not pay interest. Instead, the securities offer the potential for a return at maturity based on the performance of the worst performing of the underlyings specifiedbelow from its initial underlying value to its final underlying value.▪ If the worst performing underlying appreciates from its initial underlying value to its final underlying value, you will receive a positive return at maturity equal to that appreciationmultipliedbythe upside participation rate, subject to the maximum return at maturity specified below. However, if the worst performing underlying remains the same or depreciates from its initialunderlying value to its final underlying value, you will be repaid the stated principal amount of your securities at maturity but will not receive any return on your investment. Even if the worstperforming underlying appreciates from its initial underlying value to its final underlying value, so that you do receive a positive return at maturity, there is no assurance that your total returnat maturity on the securities will compensate you for the effects of inflation or be as great as the yield you could have achieved on a conventional debt security of ours of comparablematurity.▪ In exchange for the possibility of a positive return at maturity based on the performance of the underlying and repayment of the principal amount even if the worst performing underlyingdepreciates, investors in the securities must be willing to forgo (i) any return on the securities in excess of the maximum return at maturity and (ii) dividends with respect to any underlying.If the worst performing underlying does not appreciate from its initial underlying value to its final underlying value, you will not receive any return on your investment in thesecurities.▪ You will be subject to risks associated with each of the underlyings and will be negatively affected by adverse movements in any one of the underlyings. ▪In order to obtain the modified exposure to the worst performing underlying that the securities provide, investors must be willing to accept (i) an investment that may have limited or noliquidity and (ii) the risk of not receiving any amount due under the securities if we and Citigroup Inc. default on our obligations.All payments on the securities are subject to the creditrisk of Citigroup Global Markets Holdings Inc. and Citigroup Inc. For each underlying, its closing value on the valuation date The maximum return at maturity will be determined on the pricing date and will be at least $69.00 per security (at least 6.90% of the stated principalamount). The payment at maturity per security will not exceed the stated principal amount plus the maximum return at maturity. (1) Citigroup Global Markets Holdings Inc. currently expects that the estimated value of the securities on the pricing date will be at least $938.00 per security, which will be less than the issue price. Theestimated value of the securities is based on CGMI’s proprietary pricing models and our internal funding rate. It is not an indication of actual profit to CGMI or other of our affiliates, nor is it an indication ofthe price, if any, at which CGMI or any other person may be willing to buy the securities from you at any time after issuance. See “Valuation of the Securities” in this pricing supplement.(2) CGMI will receive an underwriting fee of up to $5.50 for each security sold in this offering. The total underwriting fee and proceeds to issuer in the table above give effect to the actual total underwritingfee. For more information on the distribution of the securities, see “Supplemental Plan of Distribution” in this pricing supplement. In addition to the underwriting fee, CGMI and its affiliates may profit fromexpected hedging activity related to this offering, even if the value of the securities declines. See “Use of Proceeds and Hedging” in the accompanying prospectus.(3) The pe