ACI Worldwide: the history behind payments software

ACI Worldwide was founded in Omaha in 1975 and built software for electronic payments on Tandem, now HPE NonStop, systems.

How ACI Worldwide developed

Its BASE24 platform became widely used for processing ATM and card transactions. ACI expanded into real-time payments, merchant services, bill payment and fraud management while serving banks and payment networks around the world.

ACI Worldwide in 2026

By 2026, ACI provided software for processing and orchestrating digital payments across banks, merchants and billers.

ACI’s longevity reflects a basic feature of payments infrastructure: once software is embedded in high-volume, always-on transaction systems, reliability and backwards compatibility become as important as new features.

Information was checked against public company material, regulatory filings and reputable independent reporting where available, using sources accessible on 18 September 2026.