CSMS 51909545·System update·May 16, 2022·View on csms.cbp.gov ↗

ACE Modernized Portal Production Maintenance Window on

Plain-English explanation

CSMS 51909545 is a U.S. Customs and Border Protection (CBP) Cargo Systems Messaging Service bulletin (system update), published on May 16, 2022. It carries the official CBP guidance brokers and importers must follow for the topic — "ACE Modernized Portal Production Maintenance Window on". 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 #51909545 - ACE Modernized Portal Production Maintenance Window on 05/16/2022 from 9:00pm to 11:00pm EST U.S. Customs and Border Protection sent this bulletin at 05/16/2022 04:22 PM EDT Cargo Systems Messaging Service CSMS #51909545 - ACE Modernized Portal Production Maintenance Window on 5/16/2022 from 9:00pm to 11:00pm ET ACE Modernized Portal Production Maintenance Window on 05/16/2022 from 9:00pm to 05/16/2022 11:00pm ET. You may be unable to access the Modernized Portal during this time. If after the window you are unable to access the portal, please close your browser, clear your cache, and try again. 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 51909545?

CSMS 51909545 is a U.S. Customs and Border Protection (CBP) Cargo Systems Messaging Service bulletin titled "ACE Modernized Portal Production Maintenance Window on". 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 51909545 published?

CBP published CSMS 51909545 on May 16, 2022. 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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