ACH File Format and NACHA File Example
A NACHA ACH file is a fixed-width text file. Every physical record is exactly 94 printable ASCII characters. Files are padded with all-9 records to a multiple of ten lines.
Use this page as an interactive NACHA file format example. Hover each field, inspect record types 1, 5, 6, 7, 8, and 9, and download the fictional sample file.
File Header
Identifies the destination and origin, file creation time, blocking factor, and format code.
Hover a highlighted field to inspect it.
Entry hash
Add the first eight digits of every receiving DFI identification from entry detail records. Keep only the lowest ten digits of that sum. Batch control (positions 11–20) and file control (positions 22–31) must match.
In the sample file, the batch control entry hash is 0000198100 and the credit total is 0000000013023 cents ($130.23).
Block padding
ACH files are blocked in groups of ten 94-character records. If the logical records do not fill the last block, the file ends with one or more lines containing only the digit 9.
This sample contains ten physical records: six logical records plus four all-9 padding lines.
Record order in a credits-only file
- File Header (type 1)
- Batch Header (type 5)
- One or more Entry Detail records (type 6)
- Optional Addenda records (type 7) after entries that need them
- Batch Control (type 8)
- File Control (type 9)
- Blocking padding lines containing only the digit 9
What this example does not prove
Banks can require different header values, naming, testing steps, and effective-date rules. This guide explains public NACHA layout concepts but does not claim independently verified compliance or guarantee bank acceptance.
Next steps
Validate an ACH file, download the import template, or create a file from Excel or CSV.