花旗集团美股招股说明书(2026-03-24版)

This Amended and Restated Pricing Supplement No. 2026-USNCH31138 is being filed to revise the final barriervalue and premium.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 and Exchange Commission. This preliminary pricingsupplement and the accompanying product supplement, underlying supplement, prospectus supplement and prospectusare not an offer to sell these securities, nor are they soliciting an offer to buy these securities, in any state where the offeror sale is not permitted.SUBJECT TO COMPLETION, DATED MARCH 23, 2026Citigroup Global Markets HoldingsMarch, 2026 Medium-Term Senior Notes, Series NAmended and Restated Pricing Supplement No.2026-USNCH31138Filed Pursuant to Rule 424(b)(3)Registration Statement Nos. 333-293732 and 333-293732-02Autocallable Securities Linked to the S&P 500 Futures 35% Edge Volatility 6% Decrement Index Inc. (USD) ER Due April 3, 2036 ▪The securities offered by this pricing supplement are unsecured debt securities issued by Citigroup Global MarketsHoldings Inc. and guaranteed by Citigroup Inc. Unlike conventional debt securities, the securities do not pay interest,do not guarantee the repayment of principal at maturity and are subject to potential automatic early redemption on aperiodic basis on the terms described below. Your return on the securities will depend on the performance of theunderlying specified below.▪The securities offer the potential for automatic early redemption at a premium following the first valuation date (other than the final valuation date) on which the closing value of the underlying is greater than or equal to the initialunderlying value. If the securities are not automatically redeemed prior to maturity, the securities will provide forrepayment of the stated principal amountplusa premium at maturity if the final underlying value is greater than orequal to the final barrier value.However, if the securities are not automatically redeemed prior to maturity andthe final underlying value is less than the final barrier value, you will lose 1% of the stated principal amount ofyour securities for every 1% by which the final underlying value is less than the initial underlying value.Although you will have downside exposure to the underlying, you will not receive dividends with respect to theunderlying or participate in any appreciation of the underlying.▪The underlying is highly risky because it may reflect highly leveraged exposure to any decline in the S&P 500Futures Excess Return Index. The S&P 500 Futures Excess Return Index tracks futures contracts on the S&P500®Index and is likely to underperform the S&P 500®Index because of an implicit financing cost. Inaddition, the underlying is subject to a decrement of 6% per annum, which will be a significant drag on itsperformance. You should carefully review the section “Summary Risk Factors—Risks relating to the S&P 500Futures 35% Edge Volatility 6% Decrement Index (USD) ER” in this pricing supplement.▪Investors in the securities must be willing to accept (i) an investment that may have limited or no liquidity and (ii) therisk of not receiving any payments due under the securities if we and Citigroup Inc. default on our obligations.Allpayments on the securities are subject to the credit risk of Citigroup Global Markets Holdings Inc. andCitigroup Inc.KEY TERMS Issuer:Citigroup Global Markets Holdings Inc., a wholly owned subsidiary of Citigroup Inc.Guarantee:All payments due on the securities are fully and unconditionally guaranteed by Citigroup Inc.Underlying:The S&P 500 Futures 35% Edge Volatility 6% Decrement Index (USD) ERStated principalamount:$1,000 per securityPricing date:March 26, 2026Issue date:March 31, 2026Valuation dates:September 30, 2026, December 31, 2026, March 31, 2027, June 30, 2027, September 30, 2027,December 31, 2027, March 31, 2028, June 30, 2028, October 2, 2028, January 2, 2029, April 2,2029, July 2, 2029, October 1, 2029, December 31, 2029, April 1, 2030, July 1, 2030, September30, 2030, December 31, 2030, March 31, 2031, June 30, 2031, September 30, 2031, December31, 2031, March 31, 2032, June 30, 2032, September 30, 2032, December 31, 2032, March 31,2033, June 30, 2033, September 30, 2033, January 3, 2034, March 31, 2034, June 30, 2034,October 2, 2034, January 2, 2035, April 2, 2035, July 2, 2035, October 1, 2035, December 31,2035 and March 31, 2036 (the “final valuation date”), each subject to postponement if such dateis not a scheduled trading day or certain market disruption events occurMaturity date:Unless earlier redeemed, April 3, 2036Automatic earlyredemption:If, on any valuation date prior to the final valuation date, the closing value of the underlying isgreater than or equal to the initial underlying value, the securities will be automatically redeemedon the fifth business day immediately following that valuation date for an amount in c