Customs Assigned Importer Number (CAIN)

Customs Assigned Importer Number (CAIN) is an importer identification number assigned by U.S. Customs and Border Protection in applicable circumstances, including certain importers without a U.S. tax identification number.

Published by AllwayforwardUpdated 18 Oct 2026

Understand it in practice

A visual breakdown of Customs Assigned Importer Number (CAIN): Importer identity, CBP-assigned identifier and Entry records. The illustration simplifies the concept; the definition and applicable terms determine the details.

Where it fits in the journey

Highlighted stages are commonly relevant

01Agree — commonly relevant
02Prepare
03Transport
04Clear — commonly relevant
05Deliver

THE PICTURE, IN WORDS

Customs Assigned Importer Number (CAIN) at a glance

Importer identity
CBP-assigned identifier
Entry records

THE DETAIL THAT MATTERS

Does an importer number establish eligibility for every import?

Having an identification number alone does not establish that every requirement for acting as importer of record has been met.

Three separate release checks

Check	What to confirm
Customs / agency	Required declarations, controls and release
Carrier / forwarder	Freight and document-release conditions
Terminal / warehouse	Availability, charges and collection appointment

Hand-drawn customs checkpoint and shipping documents illustrating border clearance. — Customs & duties in context · original educational illustration, not a photograph of a shipment.

Before you book

For customs & duties, have these details ready:

Product materials, use and manufacturing origin
The legal importer and appointed representative
Current destination rules and supporting records

Explore customs & duties support

Sources & further reading

U.S. CBP: tips for importers ↗

Plain-language educational guidance. The applicable contract, carrier tariff, official rules or insurance policy takes precedence. Illustrations show concepts, not a specific shipment or facility.

Published by Allwayforward as a plain-language freight reference. Examples are illustrative, not customer case studies. For a correction, send the term and supporting source.