CSMS 64347680·Operational·March 7, 2025·View on csms.cbp.gov ↗

UPDATE: Harmonized System Update (HSU) 2509

Plain-English explanation

CSMS 64347680 is a U.S. Customs and Border Protection (CBP) Cargo Systems Messaging Service bulletin (operational), published on March 7, 2025. It carries the official CBP guidance brokers and importers must follow for the topic — "UPDATE: Harmonized System Update (HSU) 2509". 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 # 64347680 - UPDATE: Harmonized System Update (HSU) 2509 U.S. Customs and Border Protection sent this bulletin at 03/07/2025 05:06 PM EST Cargo Systems Messaging Service CSMS # 64347680 - UPDATE: Harmonized System Update (HSU) 2509 Harmonized System Update (HSU) 2509 was created on March 7, 2025, and contains 217 Harmonized Tariff records and 651 ABI records. HSU 2509 includes the recent Canada and Mexico tariff updates. Reminder : As of March 7, 2025, the temporary exclusion from the additional ad valorem IEEPA duties in place for in-transit shipments has ended. Consequently, HTS 9903.01.23 is no longer available for merchandise entered for consumption, or withdrawn from warehouse for consumption, after 12:01 a.m. ET on March 7, 2025. All shipments that are country of origin China and Hong Kong are required to submit the 9903.01.24 tariff as well as remit payment of the additional 20% duty, unless the shipment meets the other exclusions (donation, information materials, Chapter 98). For more information on the Canada, Mexico and China tariff updates, refer to the following CSMS message: 64336037. Questions or concerns about the HSU should be directed to HTSadmin@cbp.dhs.gov . 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 64347680?

CSMS 64347680 is a U.S. Customs and Border Protection (CBP) Cargo Systems Messaging Service bulletin titled "UPDATE: Harmonized System Update (HSU) 2509". 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 64347680 published?

CBP published CSMS 64347680 on March 7, 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.

Learn more

Tandom guides relevant to CBP CSMS messages

Subscribe to and triage CBP CSMS messages

How to subscribe to CBP Cargo Systems Messaging Service and triage the messages that change broker filing behavior, without losing the ones that matter.

Open resource

Real-time alerts when a CSMS message changes a duty rate

Set up alerts when a CBP CSMS message changes a duty rate on an HTS code you depend on. Built for brokers, forwarders, and importer compliance teams.