Each data field is categorized as to the need for inclusion of data in that field. The three categories: Mandatory, Required, and Optional.

Mandatory:

Any Mandatory field not included in an ACH entry will cause that entry, batch or file to be rejected and returned. A mandatory field is necessary to ensure the proper routing and/or posting of an ACH entry.

Required:

The omission of a Required field may cause an entry to be rejected. An example is the account number field in the Entry Detail Record. If this field is omitted, the receiving bank may return the entry as unable to be posted. Fields classified as required should be included by the originator to avoid processing and control problems at the receiving bank.

Optional:

The inclusion or omission of an Optional data field is at the discretion of the Originator and will not impact the processing of an ACH entry.