CSMS 63746323·Operational·January 14, 2025·View on csms.cbp.gov ↗

UPDATE: Section 321 Warning (Release 2) Will Deploy on a Future Date

Plain-English explanation

CSMS 63746323 is a U.S. Customs and Border Protection (CBP) Cargo Systems Messaging Service bulletin (operational), published on January 14, 2025. It carries the official CBP guidance brokers and importers must follow for the topic — "UPDATE: Section 321 Warning (Release 2) Will Deploy on a Future Date". CSMS messages are the operational layer between Commerce determinations and at-the-border collections: when Commerce publishes a new rate, scope ruling, or instruction, CBP turns it into a CSMS that ACE/ACS systems and brokers act on.

Message body

Full text as published by U.S. Customs and Border Protection

CSMS # 63746323 - UPDATE: Section 321 Warning (Release 2) Will Deploy on a Future Date U.S. Customs and Border Protection sent this bulletin at 01/14/2025 05:31 PM EST Cargo Systems Messaging Service CSMS # 63746323 - UPDATE: Section 321 Warning (Release 2) Will Deploy on a Future Date U.S. Customs and Border Protection (CBP) is continuing solution testing for the second release of the Section 321 – Does Not Exceed $ 800 in Aggregated Shipments enhancement to the Automated Commercial Environment (ACE). The release will not be deployed today, January 14, 2025. After further testing, CBP will provide a status update via CSMS. For more information about the Section 321 warning, which was originally scheduled to deploy January 11, 2025, review the trade information notice: Section 321 – Does not exceed $ 800 in Aggregated Shipments – Release 2 . Related CSMS: 63705053 , 63650246 , 63737318 Update your subscriptions, modify your password or e-mail address, or stop subscriptions at any time on your Subscriber Preferences Page . You will need to use your e-mail address to log in. If you have questions or problems with the subscription service, please contact subscriberhelp.govdelivery.com . This service is provided to you at no charge by U.S. Customs and Border Protection . Privacy Policy | GovDelivery is providing this information on behalf of U.S. Department of Homeland Security, and may not use the information for any other purposes. Powered by Privacy Policy | Cookie Statement | Help

Frequently asked questions

What is CSMS 63746323?

CSMS 63746323 is a U.S. Customs and Border Protection (CBP) Cargo Systems Messaging Service bulletin titled "UPDATE: Section 321 Warning (Release 2) Will Deploy on a Future Date". CSMS bulletins are the operational instructions CBP issues to brokers, importers, and ACE filers covering rate changes, system updates, scope guidance, and other day-to-day customs-operations changes.

When was CSMS 63746323 published?

CBP published CSMS 63746323 on January 14, 2025. The bulletin's instructions are typically operative as of the publication date unless the body specifies a different effective date.

Is the CBP CSMS the legally binding instruction?

Yes — for at-the-border filing and entry collection. CSMS messages translate Commerce's Federal Register determinations into operational CBP instructions that ACE/ACS systems and brokers execute. The Federal Register notice is the underlying legal authority; the CSMS is the operational implementation. Both should be read together when reconciling a rate or scope change.

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