CSMS 66311990·Operational·September 22, 2025·View on csms.cbp.gov ↗

UPDATED GUIDANCE: Payment of Duty on International Mail Shipments pursuant to Executive Order 14324 “Suspending Duty

Plain-English explanation

CSMS 66311990 is a U.S. Customs and Border Protection (CBP) Cargo Systems Messaging Service bulletin (operational), published on September 22, 2025. It carries the official CBP guidance brokers and importers must follow for the topic — "UPDATED GUIDANCE: Payment of Duty on International Mail Shipments pursuant to Executive Order 14324 “Suspending Duty". 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 # 66311990 - UPDATED GUIDANCE: Payment of Duty on International Mail Shipments pursuant to Executive Order 14324 “Suspending Duty-Free De Minimis Treatment for All Countries” U.S. Customs and Border Protection sent this bulletin at 09/22/2025 02:57 PM EDT Cargo Systems Messaging Service CSMS # 66311990 - UPDATED GUIDANCE: Payment of Duty on International Mail Shipments pursuant to Executive Order 14324 “Suspending Duty-Free De Minimis Treatment for All Countries” Pursuant to the EO 14324 of July 30, 2025, (“ Suspending Duty-Free De Minimis Treatment for All Countries ”), effective August 29, 2025, de minimis duty-free treatment under 19 U.S.C. § 1321(a)(2)(C) will no longer be available for shipments entering into the United States not covered by 50 U.S.C. § 1702(b), including those entering through international mail. This updated guidance provides detailed instructions for transportation carriers and qualified parties on how to comply with the requirements for international mail, addresses liability for non-compliant shipments, and details the review and approval process for those applying to act as a Qualified Party for the transmission of international postal data and payment of duties. Any questions regarding this guidance can be sent to: CBPDM@cbp.dhs.gov . Related messages: CSMS # 65029543, CSMS # 65934463, CSMS # 66002708, CSMS # 65990231, CSMS # 66033571 IMD Duty Worksheet - August 2025 Release.xlsx Updated - Global Guidance for International Mail - 9.22.25.pdf 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 66311990?

CSMS 66311990 is a U.S. Customs and Border Protection (CBP) Cargo Systems Messaging Service bulletin titled "UPDATED GUIDANCE: Payment of Duty on International Mail Shipments pursuant to Executive Order 14324 “Suspending Duty". 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 66311990 published?

CBP published CSMS 66311990 on September 22, 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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