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Container Seal
Definition
A container seal is a numbered, tamper-evident device locked through a container's door hardware after loading, so anyone receiving the box can check that it was not opened on the way.
What it means
CBP's CTPAT security criteria require shipments that can be sealed to be secured immediately after loading with a high-security seal that "meets or exceeds the most current International Organization for Standardization (ISO) 17712 standard."[1] The seal number is recorded on the shipping documents.
CTPAT teaches a four-step check, VVTT: view the seal and locking mechanisms, verify the seal number against the documents, tug the seal, and twist and turn a bolt seal to be sure it does not unscrew. For discrepancies it says to keep altered or tampered seals, investigate, and report compromised seals to CBP as applicable.[1]
Example
A receiver checks the bolt seal on an arriving container: it is intact, the number matches the bill of lading, and it does not turn when twisted. The number and a photo are logged before the seal is cut.
Related
Related terms
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Related questions
- What Should I Do If a Container Seal Is Broken or Does Not Match?Stop before opening the doors. Photograph the seal and the doors, compare the seal number with the bill of...Answer
- How Is Freight Loaded into a Container for Export?Plan the load before the container arrives: stay within the container's payload and the road limits, spread...Answer
Sources
- U.S. Customs and Border Protection, “CTPAT Minimum Security Criteria, U.S. Importers (October 2021),” Government program criteria. Published October 2021. Accessed September 30, 2026.
General operational information, not legal, customs or regulatory advice. Rules and rates change; confirm current requirements with the agency, carrier or contract that governs your shipment.