ACH is a computer-based clearing and settlement facility established to process the exchange of electronic transactions between participating depository institutions. Rules and regulations that govern the ACH network are established by NACHA and the Federal Reserve.In 2013, this network processed nearly 22 billion ACH transactions with a total value of $38.7 trillion. Credit card payments are handled by separate networks.he Federal Reserve Banks, through the FedACH system, are collectively the nation's largest ACH operator. In 2005, they processed 60% of commercial interbank ACH transactions; the remaining 40% was processed by the Electronic Payments Network (EPN), the United States' only private-sector ACH operator.