Outbound ACH Transfers

ACH Transfers are the dominant low-value transfer mechanism in the US. Increase processes billions of dollars of ACH transfers each year using our ACH Transfer API.

Details about receiving an ACH Transfer are described here.

Sending an ACH Transfer

Originating an ACH transfer via the Increase API kicks off several steps involving you, Increase, the Federal Reserve, and the receiving bank.

  1. You make a POST /ach_transfers call with the details of how much you'd like to credit or debit and data about the recipient.
  2. If your account is configured to require approval for transfers, a Pending Transaction is created and an approver will need to approve the transfer. After this point, the transfer cannot be canceled.
  3. Roughly every 30 minutes, Increase submits all the pending ACH transfers to the Federal Reserve in a single file. Increase updates the ACH Transfer object with its submission details.
  4. The Federal Reserve acknowledges the file. This generally happens within fifteen minutes of file submission. Increase updates the ACH Transfer object with its acknowledgement details.
  5. The Federal Reserve forwards transfer details to the receiving bank several times per day. The predicted settlement time when is in submission.expected_funds_settlement_at. There may be delays and processing time required at the receiving bank, however.

ACH transfers work based on a principle of assumed success. There's no positive acknowledgement from a receiving bank confirming that they've received and allocated the transfer to one of their customer's accounts.


When a bank cannot or will not honor an ACH transfer, they create an ACH return. An ACH transfer to a business account can be returned for up to two business days. An ACH transfer to a consumer account can be return for up to 60 days. Common return reasons are insufficient funds or a lack of authorization.

Only if the counterparty bank returns the ACH, there is a final step:

  1. The ACH Transfer's status changes to returned and the relevant data are stored in the return details.

Funds holds

To help you avoid double-spending funds received by an ACH Debit, Increase automatically creates a funds hold. The funds hold is released when the 2 business day return window has passed.

There are no funds holds for ACH credits, when you send money to a counterparty. Your Increase account balance will immediately decrement (and is correspondingly incremented when the ACH is returned).