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  1. Home
  2. Trade
  3. ACE and Automated Systems
  4. Technical Documentation

Technical Documentation for All CBP Automated Systems

These pages linked below provide the message formats and technical specifications necessary to electronically transmit data to CBP's automated systems, along with scheduled system outages that affect testing of software.

ACE Technical Documentation

Legacy System Documentation

These links contain detailed requirements for filing information to legacy systems including Automated Commercial System (ACS) and Automated Broker Interface (ABI) CATAIR technical requirements.

ACE Outage Schedules

There are two ACE environments available to the trade – Certification (CERT) and Production (PROD).

  • The production environment is the day-to-day live ACE environment used to process import and export submissions.

  • The certification environment is for trade users to test ACE capabilities prior to filing in the production environment.

Both environments are subject to both planned and unplanned outages. Planned outages are scheduled to conduct routine maintenance, while unplanned outages are to address critical system issues. Outages to the ACE Certification environment only impact parties testing software.

Environment Outage Window(s)
Certification As Needed during non-business hours
(i.e. from 5:30 PM – 8:30 AM)
  • Tuesday 5 AM – 7 AM – outage should be no more than 30 minutes
  • Thursday 5 AM – 7 AM – outage should be no more than 30 minutes
  • Saturday 10 PM – Sunday 4 AM – used for outages expected to be more than 30 minutes

System outages are announced through the Cargo Systems Messaging Service. To subscribe, please visit the CSMS subscription page.


  • Last Modified: September 29, 2022