Exhibit 99.1 ACI Worldwide Reports Strong First Quarter 2026 Results and Raises Full-Year Guidance Q1 2026 HIGHLIGHTS Omaha, NE — May 7, 2026 — ACI Worldwide (NASDAQ: ACIW), a leading provider of global payments technology, today announced financial results for the quarter ended March 31, 2026. "Payments modernization continues to accelerate, and ACI is at the center of it," said Thomas Warsop, President and CEO of ACI Worldwide. "In the quarter, Real Time Payments and Merchant each grew more than 20%, Bill ...