ACH transfers work by batching together multiple transactions and processing them at specific intervals. This process involves the following steps: 1. Initiation: The originator (business or individual) requests a transfer. 2. Batching: The bank collects multiple transfer requests into a batch. 3. Clearing: The batch is sent to the ACH operator, who sorts and distributes the transactions. 4. Settlement: Funds are transferred between banks, and the transactions are completed.