Free Writing Prospectus (Form FWP)

Filed Pursuant to Rule 433

Registration Statement No. 333-277241

June 16, 2026

Final Term Sheet

Fiserv, Inc.

€1,000,000,000 aggregate size, consisting of:

€500,000,000 3.750% SENIOR NOTES DUE 2030 (the "2030 Notes")

€500,000,000 4.250% SENIOR NOTES DUE 2034 (the "2034 Notes")

(together, the "Notes")

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The Issuer has filed a Registration Statement (including a prospectus) and a preliminary prospectus supplement with the Securities and Exchange Commission (the "SEC") for the offering to which this communication relates. Before you invest, you should read the prospectus in that registration statement, the preliminary prospectus supplement and other documents the Issuer has filed with the SEC for more complete information about the Issuer and this offering. You may get these documents for free by visiting EDGAR on the SEC website at www.sec.gov. Alternatively, the Issuer, any underwriter or any dealer participating in the offering will arrange to send you the prospectus and preliminary prospectus supplement if you request it by calling Citigroup Global Markets Limited at +1-800-831-9146, J.P. Morgan Securities plc at +44 20 7134-2468 (Non-U.S. investors) or collect at +1-212-834-4533 (U.S. investors), TD Global Finance unlimited company at +44 20 7628-2262 or Wells Fargo Securities International Limited at +44 20 3942-8538.

Relevant stabilization regulations including FCA/ICMA will apply.

The Notes will be represented by beneficial interests in fully registered permanent global notes (the "global notes") without interest coupons attached, which will be registered in the name of, and shall be deposited on or about June 23, 2026 with a common depositary for, and in respect of interests held through, Euroclear Bank, S.A./N.V., as operator of the Euroclear System ("Euroclear"), and Clearstream Banking, société anonyme ("Clearstream"). Any Notes

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represented by global notes held by a nominee of Euroclear or Clearstream will be subject to the then applicable procedures of Euroclear and Clearstream, as applicable. Euroclear and Clearstream's current practice is to make payments in respect of global notes to participants of record that hold an interest in the relevant global notes at the close of business on the date that is the clearing system business day (for these purposes, Monday to Friday inclusive except December 25th and January 1st) immediately preceding each applicable interest payment date.

Prohibition of Sales to EEA Retail Investors: The Notes are not intended to be offered, sold, distributed or otherwise made available to and should not be offered, sold, distributed or otherwise made available to any retail investor in the European Economic Area ("EEA"). For these purposes, (a) the expression "retail investor" means a person who is one (or more) of: (i) a retail client as defined in point (11) of Article 4(1) of Directive 2014/65/EU (as amended, "MiFID II"); (ii) a customer within the meaning of Directive (EU) 2016/97 (as amended, the "Insurance Distribution Directive"), where that customer would not qualify as a professional client as defined in point (10) of Article 4(1) of MiFID II; or (iii) not a qualified investor as defined in Article 2(e) of Regulation (EU) 2017/1129 (as amended, the "Prospectus Regulation"); and (b) the expression "offer" includes the communication in any form and by any means of sufficient information on the terms of the offer and the securities to be offered so as to enable an investor to decide to purchase or subscribe for such securities. Consequently, no key information document required by Regulation (EU) No 1286/2014 (as amended, the "PRIIPs Regulation") for offering, selling or distributing the Notes or otherwise making them available to retail investors in the EEA has been prepared and therefore offering, selling or distributing the Notes or otherwise making them available to any retail investor in the EEA may be unlawful under the PRIIPs Regulation.

MiFID II professionals/ECPs-only: Manufacturer target market (MiFID II product governance) is eligible counterparties and professional clients only (all distribution channels). Any person subsequently offering, selling or recommending the Notes (a "distributor") should take into consideration the manufacturers' target market assessment; however, a distributor subject to MiFID II is responsible for undertaking its own target market assessment in respect of the Notes (by either adopting or refining the manufacturers' target market assessment) and determining appropriate distribution channels.

Prohibition of Sales to UK Retail Investors: The Notes are not intended to be offered, sold, distributed or otherwise made available to and should not be offered, sold, distributed or otherwise made available to any retail investor in the United Kingdom ("UK"). For these purposes, (a) the expression "retail investor" means a person who is one (or both) of the following: (i) not a "professional client", as defined in point (8) of Article 2(1) of Regulation (EU) No 600/2014 as it forms part of assimilated law in the UK by virtue of the European Union (Withdrawal) Act 2018 (as amended, and together with any statutory instruments made in exercise of the powers conferred by such Act, the "EUWA"); or (ii) not a "qualified investor" as defined in paragraph 15 of Schedule 1 to The Public Offers and Admissions to Trading Regulations 2024 ("POATRs"); and (b) the expression "offer" includes the communication in any form and by any means of sufficient information on the terms of the offer and the securities to be offered so as to enable an investor to decide to buy or subscribe for such securities. Consequently, no disclosure document required by the FCA Product Disclosure Sourcebook (the "DISC Sourcebook") for offering, selling or distributing the Notes or otherwise making them available to retail investors in the UK has been prepared and therefore offering, selling or distributing the Notes or otherwise making them available to any retail investor in the UK may be unlawful under the DISC Sourcebook and The Consumer Composite Investments (Designated Activities) Regulations 2024.

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United Kingdom MiFIR professionals/ECPs-only: Manufacturer target market (FCA Handbook Product Intervention and Product Governance Sourcebook (the "UK MiFIR Product Governance Rules")) is eligible counterparties and professional clients only (all distribution channels). Any distributor should take into consideration the manufacturers' target market assessment; however, a distributor subject to UK MiFIR Product Governance Rules is responsible for undertaking its own target market assessment in respect of the Notes (by either adopting or refining the manufacturers' target market assessment) and determining appropriate distribution channels.

ANY DISCLAIMER OR OTHER NOTICE THAT MAY APPEAR BELOW IS NOT APPLICABLE TO THIS COMMUNICATION AND SHOULD BE DISREGARDED. SUCH DISCLAIMER OR NOTICE WAS AUTOMATICALLY GENERATED AS A RESULT OF THIS COMMUNICATION BEING SENT BY BLOOMBERG OR ANOTHER EMAIL SYSTEM.

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