How to track a container

You can follow an ocean shipment with three references: the container number, the bill of lading (BL) number or the booking number. This guide explains where to find each one, how to track it, and what each step of the journey means.

1. Find your reference

The container number (4 letters and 7 digits, for example CSQU3054383) is painted on the container doors and printed on the bill of lading, the packing list and the arrival notice. Its format is explained in Container number format (ISO 6346).

The bill of lading number is printed on the bill of lading or sea waybill, usually at the top. The booking number is on the booking confirmation the carrier sends when space is reserved. The differences are explained in Booking number vs bill of lading vs container number.

2. Identify the carrier

Tracking happens at the carrier that moves the container, so you need to know which one it is. The first four letters of a container number often point to the carrier that owns it, but many containers are leased and carry a leasing company's code. A master bill of lading usually starts with the carrier's 4-letter SCAC code. A booking number usually has no prefix, so you need to know the carrier.

Each carrier page lists the codes and formats that carrier uses, for example Maersk, COSCO or ONE.

3. Track it

On a carrier's website you enter one reference at a time and come back later to see what changed. With BerthTime you paste a container, BL or booking number: it detects the type and the carrier, collects the events into one timeline, refreshes it and alerts you when the ETA moves. A BL or booking brings in all its containers. Start a free trial or see the container tracking overview.

What each milestone means

Carriers name the steps differently, but a typical export-to-import journey looks like this:

• Empty container released (gate-out empty): the empty container leaves the depot to be loaded (stuffed) at the shipper's premises.
• Gate-in: the loaded container enters the terminal at the port of loading.
• Loaded: the container is lifted on board the vessel.
• Vessel departure: the vessel leaves the port of loading.
• Transshipment: the container is discharged at an intermediate port and loaded on another vessel. A shipment can have several.
• Vessel arrival: the vessel reaches the port of discharge.
• Discharged: the container is lifted off the vessel at the port of discharge.
• Gate-out: the full container leaves the terminal for delivery to the consignee, once it is released.
• Empty return: the empty container goes back to the carrier's depot.

Actual and estimated times, and the ETA

Steps that have happened carry an actual time; future steps carry an estimated time that the carrier can change. The ETA is the estimated time of arrival at the port of discharge, and it moves when the vessel is delayed or the schedule changes. BerthTime also shows a predicted arrival computed from the vessel's AIS position when the vessel is identified, always labelled as an estimate.

When the reference is not found

• Check for typos. A container number has a check digit, so most typos can be spotted (see the checker in the ISO 6346 guide).
• It may be too early: a new booking can take a while to appear in the carrier's tracking.
• A house bill of lading from a forwarder is not known to the carrier. Ask for the master BL or the container numbers (see What is a bill of lading number).
• A leased container may be operated by a different carrier than its code suggests: choose the carrier yourself.