The Automated Clearing House (ACH) is an electronic network (otherwise known as ACH network) that connects more than 25,000 banks and financial institutions in the United States. This allows for the electronic transfer of funds across accounts, making payments quicker and simpler. There are two types of ACH transactions: An ACH is an electronic fund transfer made between banks and credit unions across what is called the Automated Clearing House network. ACH is used for all kinds of fund transfer transactions, including direct deposit of paychecks and monthly debits for routine payments. An automated clearing house ( ACH) is a computer-based electronic network for processing transactions, [1] usually domestic low value payments, between participating financial institutions. It may support both credit transfers and direct debits. sKwrPL.