CSMS 64397102·Operational·March 12, 2025·View on csms.cbp.gov ↗

Harmonized System Update (HSU) 2510 and 2511

Plain-English explanation

CSMS 64397102 is a U.S. Customs and Border Protection (CBP) Cargo Systems Messaging Service bulletin (operational), published on March 12, 2025. It carries the official CBP guidance brokers and importers must follow for the topic — "Harmonized System Update (HSU) 2510 and 2511". 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 # 64397102 - Harmonized System Update (HSU) 2510 and 2511 U.S. Customs and Border Protection sent this bulletin at 03/12/2025 04:01 PM EDT Cargo Systems Messaging Service CSMS # 64397102 - Harmonized System Update (HSU) 2510 and 2511 Harmonized System Update (HSU) 2510 was created on March 11, 2025, and contains 17 Harmonized Tariff Records and 43 ABI records. Harmonized System Update (HSU) 2511 was created on March 12, 2025, and contains 2 Harmonized Tariff Records and 5 ABI records. HSU 2510 includes the latest adjustments on imports of steel and aluminum into the United States. For additional information please refer to FRN 2025-02833 and FRN 2025-02832 . HSU 2511 includes corrections to UOM for Steel (9903.81.91) and Aluminum (9903.85.08) For additional steel filling information, reference CSMS 64348411 . For additional aluminum filing information, reference CSMS 64348288 . Questions regarding the new tariffs, should be referred to the Trade Remedy Branch at TradeRemedy@cbp.dhs.gov. Questions or concerns with the Harmonized System Update should be directed to the HTS admin at HTSadmin@cbp.dhs.gov . In support of the PGA Message Set, Participating Government Agency (PGA), FDA tariff flags on eight HTS codes under heading 1207 from FD4 to FD3 were updated. Questions or concerns for PGA HTS Flagging should be emailed to itdssupport@cbp.dhs.gov . Questions or concerns with the Harmonized System Update should be directed to HTS admin at HTSAdmin@cbp.dhs.gov . Questions or concerns about PGA HTS Flagging should be emailed to itdssupport@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 64397102?

CSMS 64397102 is a U.S. Customs and Border Protection (CBP) Cargo Systems Messaging Service bulletin titled "Harmonized System Update (HSU) 2510 and 2511". 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 64397102 published?

CBP published CSMS 64397102 on March 12, 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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