HSBC Holdings plc $2,250,000,000 4.711% Fixed Rate/Floating Rate Senior Unsecured Notes due 2030$2,250,000,000 5.208% Fixed Rate/Floating Rate Senior Unsecured Notes due 2034 We are offering $2,250,000,000 principal amount of 4.711% Fixed Rate/Floating Rate Senior Unsecured Notes due 2030 (the “2030 Fixed/Floating Rate Notes”) and $2,250,000,000 principal amount of 5.208%Fixed Rate/Floating Rate Senior Unsecured Notes due 2034 (the “2034 Fixed/Floating Rate Notes”). The Notes (as defined below) will be issued pursuant to the indenture dated as of August26, 2009 (as amended andsupplemented from time to time, the “Base Indenture”), as amended and supplemented by a thirty-ninth supplemental indenture, which is expected to be entered into on May12, 2026 (the Base Indenture, together withthe thirty-ninth supplemental indenture, the “Indenture”). The Notes means either the 2030 Fixed/Floating Rate Notes or the 2034 Fixed/Floating Rate Notes, as applicable. From (and including) May12, 2026 (the “Issue Date”) to (but excluding) May12, 2029 we will pay interest semi-annually in arrear on the 2030 Fixed/Floating Rate Notes on May12 and November12 of eachyear, beginning on November12, 2026, at a rate of 4.711% per annum. Thereafter, we will pay interest quarterly in arrear on the 2030 Fixed/Floating Rate Notes on August12, 2029, November12, 2029, February12,2030 and May 12, 2030 at a floating rate equal to a benchmark rate based on SOFR, calculated in arrear as defined herein and compounding daily over each 2030 Fixed/Floating Rate Notes Floating Rate InterestPeriod, plus 0.940% per annum. The 2030 Fixed/Floating Rate Notes will mature on May12, 2030. From (and including) the Issue Date to (but excluding) May 12, 2033 we will pay interest semi-annually in arrear on the 2034 Fixed/Floating Rate Notes on May12 and November12 of each year, beginning onNovember12, 2026, at a rate of 5.208% per annum. Thereafter, we will pay interest quarterly in arrear on the 2034 Fixed/Floating Rate Notes on August12, 2033, November12, 2033, February12, 2034 and May12,2034 at a floating rate equal to a benchmark rate based on SOFR, calculated in arrear as defined herein and compounding daily over each 2034 Fixed/Floating Rate Notes Floating Rate Interest Period, plus 1.320% perannum. The 2034 Fixed/Floating Rate Notes will mature on May12, 2034. We may, in our sole discretion, redeem the 2030 Fixed/Floating Rate Notes (a)during the 2030 Fixed/Floating Rate Notes Make-Whole Redemption Period (as defined below), in whole at any time during suchperiod or in part from time to time during such period, at a redemption price (expressed as a percentage of principal amount and rounded to three decimal places) equal to the greater of: (i) 100% of their principalamount and (ii)a make-whole price calculated as set forth under“Description of the Notes––Redemption”(in each case plus any accrued and unpaid interest on the 2030 Fixed/Floating Rate Notes to be redeemed to(but excluding) the applicable redemption date) or (b)following the 2030 Fixed/Floating Rate Notes Make-Whole Redemption Period, pursuant to a 2030 Fixed/Floating Rate Notes Par Redemption (as defined herein),in whole but not in part, on May12, 2029 (the “2030 Fixed/Floating Rate Notes Par Redemption Date”) at a redemption price equal to 100% of their principal amount plus any accrued and unpaid interest to (butexcluding) the 2030 Fixed/Floating Rate Notes Par Redemption Date, in each case on the terms and subject to the provisions set forth under“Description of the Notes––Redemption.”The “2030 Fixed/Floating RateNotes Make-Whole Redemption Period” means the period beginning on (and including) November12, 2026 (six months following the Issue Date) to (but excluding) the 2030 Fixed/Floating Rate Notes ParRedemption Date;providedthat if any additional notes of the same series are issued after the Issue Date, the 2030 Fixed/Floating Rate Notes Make-Whole Redemption Period for such additional notes shall begin on(and include) the date that is six months following the issue date for such additional notes. We may, in our sole discretion, redeem the 2034 Fixed/Floating Rate Notes (a)during the 2034 Fixed/Floating Rate Notes Make-Whole Redemption Period (as defined below), in whole at any time during suchperiod or in part from time to time during such period, at a redemption price (expressed as a percentage of principal amount and rounded to three decimal places) equal to the greater of: (i) 100% of their principalamount and (ii)a make-whole price calculated as set forth under“Description of the Notes––Redemption”(in each case plus any accrued and unpaid interest on the 2034 Fixed/Floating Rate Notes to be redeemed to(but excluding) the applicable redemption date) or (b)following the 2034 Fixed/Floating Rate Notes Make-Whole Redemption Period, pursuant to a 2034 Fixed/Floating Rate Notes Par Redemption (as defined herein),in whole but not in part, on May12, 2033 (the “2034 Fixed/Floating R