Nacha Accelerates ACH Funds Availability and Clarifies IAT Definition

Two changes to the Nacha Operating Rules take effect September 18, 2026: they accelerate funds availability for certain non-Same Day ACH credit entries and replace the definition of International ACH Transactions ("IATs").

In the final rules, Nacha eliminated the requirement that a credit be received by 5 p.m. the prior day for the 9 a.m. funds availability deadline to apply, and updated the IAT definition to help ACH Network participants more easily determine when a payment should be classified as an IAT.

The revised funds availability rule will require receiving depository financial institutions ("RDFIs") to make all non-Same Day ACH credits available by 9 a.m. local time on the settlement date, regardless of when the RDFI receives the entry from its ACH Operator. A related rule will create a limited exception for RDFIs located east of the Atlantic Time Zone and west of the international date line, such as those in Guam and the Northern Mariana Islands. For these institutions, alternative availability requirements will apply based on when the ACH Operator makes the entry available to the RDFI.

The new rule replaces the existing IAT definition outright. An IAT is now the U.S. ACH Network component of an international payment transaction, and an IAT entry cannot be a Same Day Entry. An international payment transaction is a transfer of funds or monetary value that originates with, transits through, or is delivered to an account at an office of a financial agency outside the United States. It also covers transfers otherwise received from a sender or delivered to a receiver through a facility of a financial agency outside the United States. Nacha noted that the change could result in some payments previously treated as domestic being identified as IATs, or vice versa, which may require organizations to update their onboarding, agreement, and due diligence processes.