ACH

Automated Clearing House, the domestic batch payment network of the United States. Governed by the Nacha Operating Rules and run by two operators: FedACH, operated by the Federal Reserve, and the Electronic Payments Network, operated by The Clearing House.

It is the default way American businesses pay each other. In the second quarter of 2026 the network carried 9.3 billion payments worth 25.9 trillion US dollars (Nacha, checked September 2026).

For a business outside the United States, the defining fact is that ACH is domestic. It settles between US financial institutions and reaches no account anywhere else. When an American customer offers to "ACH you", they mean they will pay a US account.

One structural difference from a wire: an ACH payment can be returned after it has settled, within windows set by the Nacha rules.