On today's call, we will discuss ACI Worldwide's second quarter 2026 results, as well as our updated financial outlook for the remainder of the year. You can find the full text of these statements in our earnings materials and SEC filings. Today, we reported 7% revenue growth, 12% Adjusted EBITDA growth, and 54% adjusted diluted EPS growth. Perhaps even more importantly, we continued to make progress on our key strategic initiatives, the things we believe drive long-term growth and shareholder value creation.
The traction with ACI Connetic is a result of our ongoing strategic growth investments and the privileged position we have in the payments ecosystem around the world. Our margin expansion is a result of disciplined expense management while continuing to invest in innovation and returning capital to shareholders. Our ACI Connetic pipeline continues to expand faster than any other solution set. On ACI Speedpay ONE in our Biller business, we've deployed tools to simplify and accelerate our customers' ability to deploy our standard APIs and to accelerate the customer implementation journey.
Obviously, Bobby will cover more detail, but let me start with Payment Software. The segment delivered 9% revenue growth driven by strength in issuing and acquiring, where revenue increased 37%. As transaction volumes continue to grow and payment environments become more complex, customers increasingly view ACI as a strategic technology partner rather than simply a software provider. Our merchant and anti-fraud solutions both grew in the mid-single digits, and both solutions are well-positioned to benefit from some interesting new AI, which is driving new technology opportunities and tools.