ACH Acknowledge File (FedACH ACK)

What this file is for

A FedACH Acknowledge File (.ack) is the operator response after your ACH file is submitted for processing.
It is not a NACHA forward file; it is an acknowledgment report that tells you whether the file was accepted, pended, rejected, or accepted with errors.

Operationally, this file answers: “What happened to my submitted file at the operator layer?”

What type of file it is

• Fixed-width, print-style report content (not 94-char NACHA forward records).
• Usually one long text payload with padded logical lines.
• Contains status and processing metadata, plus count/amount summary.
• May contain error detail lines (for example codes like FH114 and related messages).

What information it contains

Typical field groups in ACK:

• File identity: program ID, servicing FRB, file status.
• Origin/destination: immediate origin name, immediate origin, immediate destination.
• Timing: report time, file creation date/time, file process date/time, received date/time.
• Volume and amount: batch count, entry/addenda count, debit total, credit total.
• Error context (when applicable): item/file-level error markers, error code/message, rejected-item count.
• Filename metadata: document type, origin ABA, channel code, timestamp, sequence.

Common status meanings

• FILE ACCEPTED WITH NO ERRORS: accepted cleanly.
• FILE ACCEPTED WITH ITEM LEVEL ERRORS: accepted, but specific items were rejected.
• FILE PENDED WITH FILE LEVEL ERRORS: file is held/pended pending processing path.
• FILE REJECTED: not accepted at file level.
• DUPLICATE FILE: duplicate submission detection.

Parse with FinStackCloud

Use the NACHA & ACK Inspector page and switch to FedACH ACK Inspect:

• Upload one or multiple .ack files.
• Parse entirely in browser (local-only; no server upload).
• Review parsed fields and derived fields separately.
• Inspect warnings/errors and error-detail lines for fast triage.

Open tool: NACHA & ACK Inspector