How to Resolve Common AES Response Messages

September 16, 2025

Note: This message is sent to all AES Updates subscribers and is for educational purposes only.

When submitting your Electronic Export Information (EEI) to the Automated Export System (AES), you can receive different response messages: Fatal, Compliance, Verify, Informational and Warning.  It is important that AES filers address and/or correct Response Messages as soon as they are received to comply with the Foreign Trade Regulations. 

To help you take the appropriate action, here is guidance on how to address one of the most frequent Response Messages that were generated in the AES for the previous month.

Response Code:  120

Narrative:     Carrier Unknown

Severity:       Fatal

Reason:        The Carrier ID (SCAC/IATA) reported is not known in AES.

Resolution:  For vessel, rail or truck shipments the carrier must be identified with an active SCAC code issued by the National Motor Freight Traffic Association (NMFTA).  For air shipments, the carrier must be identified with an active IATA code issued by the International Air Transport Association.

If the Carrier ID (SCAC/IATA) as known at the time of filing is not valid in AES and a valid Carrier ID (SCAC/IATA) cannot be obtained from the carrier, as a last resort, report the Carrier ID as UNKN for vessel, rail or truck shipments.  For an unknown air carrier, report one of the acceptable “unknown” codes as follows:
*F or 99F for Unknown Foreign Air Carrier
*U or 99U for Unknown U.S. Air Carrier
*C or 99C for Unknown Canadian Air Carrier
** or 99O for flyway aircraft reported under Chapter 88.

Verify the Mode of Transportation Code and the Carrier ID (SCAC/IATA), correct the shipment and resubmit.

For a complete list of the AES Response Codes, their reasons and resolutions, see Appendix A – Commodity Filing Response Messages.

As a reminder, filers have multiple resources that they can use when filing EEI to the AES.  You can access User Guides, Walk-through videos and other resources at our website.

Please contact the U.S. Census Bureau’s Trade Data Collection Branch for further information or questions.

Telephone: (800) 549-0595, select option 1 for AES

Email: askaes@census.gov

Online: www.census.gov/trade

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