花旗美股招股说明书(2026-07-02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, prospectus supplement and prospectus are not an offer to 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 JULY 1, 2026 July, 2026Medium-Term Senior Notes, Series NPricing Supplement No. 2026-USNCH32942Filed Pursuant to Rule 424(b)(2)Registration Statement Nos. 333-293732 and 333-293732-02 Citigroup Global Markets Holdings Autocallable Barrier Securities Linked to Marvell Technology, Inc. Due July 26, 2029 ▪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, do not guarantee the repayment of principal at maturity and are subject to potential automatic early redemption on the terms described below.Your return on the securities will depend on the performance of the underlying specified below.▪ The securities offer the potential for automatic early redemption at a premium following the valuation date prior to the final valuation date if the closing value of the underlying is greater thanor equal to the initial underlying value. If the securities are not automatically redeemed prior to maturity, the securities will no longer offer the opportunity to receive a premium, but instead,at maturity, will provide for (i) the opportunity to participate in any appreciation of the underlying from the initial underlying value at the upside participation rate specified below and (ii)contingent repayment of the stated principal amount at maturity if the underlying depreciates,but onlyso long as the final underlying value is greater than or equal to the final barrier valuespecified below.However, if the securities are not automatically redeemed prior to maturity and the final underlying value is less than the final barrier value, you will lose 1% ofthe stated principal amount of your securities for every 1% by which the final underlying value is less than the initial underlying value.Although you will have downside exposureto the underlying, you will not receive dividends with respect to the underlying.▪ Investors in the securities must be willing to accept (i) an investment that may have limited or no liquidity and (ii) the risk of not receiving any payments due under the securities if we andCitigroup Inc. default on our obligations.All payments on the securities are subject to the credit risk of Citigroup Global Markets Holdings Inc. and Citigroup Inc. The premium applicable to the valuation date prior to the final valuation date is the percentage of the stated principal amount indicatedbelow.The premium may be significantly less than the appreciation of the underlying from the pricing date to the valuation dateprior to the final valuation date.•July 23, 2027:70.70% of the stated principal amount ■If the final underlying value isgreater thanthe initial underlying value:$1,000 + the return amount■If the final underlying value isless than or equal tothe initial underlying value butgreater than or equal tothe final barriervalue:$1,000■If the final underlying value isless thanthe final barrier value:$1,000 + ($1,000 × the underlying return) The securities will not be listed on any securities exchange (1) Citigroup Global Markets Holdings Inc. currently expects that the estimated value of the securities on the pricing date will be at least $899.50 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 $20.00 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 underwriting fee. From this underwriting fee, CGMI will pay selected dealers not affiliated with CGMI a variable selling concession of up to $20.00 for each security they sell. In addition, CGMI will payselected dealers not affiliated with CGMI a structuring fee of up to $6.50 for each security they sell. For more information on the distribution of the securities, see “Supplemental Plan of Distribution” in thispricing supplement. In addition to the underwriting fee, CGMI and its affiliates may profit from expected hedging activity related to this offering, even i