File Format Specifications For Files From Third-Party Vendors


The following guidelines pertain to the formatting of files that are received from third-party vendors (ATM/debit card vendors, check processors, etc.) for posting to credit unions by the CU*Answers Operations staff.


The purpose of these guidelines is to ensure that files are received intact and posted accurately, and to ensure that duplicate transmissions can be detected and file integrity can be confirmed through balancing procedures.

Files that do not adhere to these standards cannot be warranted as accurate by CU*Answers Operations. If errors occur because these guidelines are not followed, any fees and charges incurred to correct the error will be the responsibility of the credit union.


The preferred format for all files received is the ACH Record Format used by the Federal Reserve.

  • Header Record
    This record is required and must include the following data:

    1. The File Date of the transmission.
    2. Process Date for the itmes in the file. For example, if Tuesday’s file is for Monday’s activity, the header should show a file date of Tuesday’s date, and a process date of Monday’s date.
  • Detail Records
    Detail records should include information needed for posting these items to the members’ accounts (account number, debit/credit amount, transaction codes, etc.) For ATM/debit card transmissions, the detail record should include the Transaction Date for all transactions included in the file.
  • Trailer Record
    This record must include the total dollar amount of all items in the file, and a total record count. These totals are critical for making sure the data that is posted matches what was in the incoming file.
  • An accompanying e-mail or fax must also be sent showing the total dollar amount and total record count, so that the file can be verified before it is posted.
September 26, 2014