Big box retailers, grocery stores, recurring billers and companies that sell via subscription handle high quantities of credit and debit card payments.  ACI Worldwide is targeting these merchants for the rollout of its Instant Pay software, which was just launched in the US and will be available in the EU and the UK next quarter. Those jurisdictions are connected to 816 million people.  ACI Instant Pay is an account-to-account (A2A) payment service that can be accessed via a single integration.