How to Resolve Common AES Response Messages

January 15, 2026

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:  503

Narrative:     License Code Missing

Severity:       Fatal

Reason:       The License Code/ License Exemption Code is missing.

Resolution: A License Code/ License Exemption Code must be reported on every shipment. 

Valid License Codes in AES are listed in Appendix F - License and License Exemption Type Codes and Reporting Guidelines. 

Verify the License Code/ License Exemption Code, 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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About the Census Bureau

We serve as the nation’s leading provider of quality data about its people and economy. The Census Bureau is the federal government's largest statistical agency. As the world’s premier statistical agency, we are dedicated to making our nation a better place. Policy-makers, businesses, and the public use our data to make informed decisions.