
December, 2025Medium-Term Senior Notes, Series NPricing Supplement No. 2025-USNCH29608Filed Pursuant to Rule 424(b)(2)Registration Statement Nos. 333-270327 and 333-270327-01 Citigroup Global Markets Holdings Autocallable Contingent Coupon Equity Linked Securities Linked to NVIDIA Corporation Due January 4, 2029 ▪The securities offered by this pricing supplement are unsecured debt securities issued by Citigroup Global Markets Holdings Inc. and guaranteed by Citigroup Inc. The securities offer thepotential for periodic contingent coupon payments at an annualized rate that, if all are paid, would produce a yield that is generally higher than the yield on our conventional debt securitiesof the same maturity. In exchange for this higher potential yield, you must be willing to accept the risks that (i) your actual yield may be lower than the yield on our conventional debtsecurities of the same maturity because you may not receive one or more, or any, contingent coupon payments, (ii) the value of what you receive at maturity may be significantly less thanthe stated principal amount of your securities, and may be zero, and (iii) the securities may be automatically called for redemption prior to maturity beginning on the first potential autocalldate specified below. Each of these risks will depend on the performance of the underlying specified below. Although you will have downside exposure to the underlying, you will not receivedividends with respect to the underlying or participate in any appreciation of 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. If the securities are not automatically redeemed prior to maturity, you will receive at maturity for each security you then hold (inaddition to the final contingent coupon payment, if applicable):■ If the securities are not automatically redeemed prior to maturity and the final underlying value is less than the finalbarrier value, you will receive underlying shares (or, in our sole discretion, cash) that will be worth significantly lessthan the stated principal amount of your securities, and possibly nothing, at maturity, and you will not receive anycontingent coupon payment at maturity. , the stated principal amountdividedby the initial underlying value (1) Citigroup Global Markets Holdings Inc. currently expects that the estimated value of the securities on the pricing date will be at least $910.50 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) The issue price for investors purchasing the securities in fee-based advisory accounts will be $972.50 per security, assuming no custodial fee is charged by a selected dealer, and up to $977.50 persecurity, assuming the maximum custodial fee is charged by a selected dealer. See “Supplemental Plan of Distribution” in this pricing supplement.(3)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. Investing in the securities involves risks not associated with an investment in conventional debt securities. See “Summary Risk Factors” beginning onpage PS-6. Product Supplement No. EA-04-10 dated March 7, 2023Prospectus Supplement and Prospectus each dated March 7, 2023The securities are not bank deposits and are not insured or guaranteed by the Federal Deposit Insurance Corporation or any other governmental agency, nor are they obligations of, or Additional Information General.The terms of the securities are set forth in the accompanying product supplement, prospectus supplement and prospectus, assupplemented by this pricing supplement. The accompanying product supplement, prospectus supplement and prospectus contain importantdisclosures that are not repeated in this pricing supplement. For example, the accompanying product supplement contains important informationabout how the closing value of the underlying will be determined and about adjustments that may be made to the terms of the securities upon theoccurrence of market disruption events and other specified events with respect