Which number you need to track a container
You can track cargo by one of three numbers — it is important to understand the difference:
- Container number — the unique code on the container itself, for example MSCU1234567. It shows the movement of a specific container.
- Bill of Lading number (B/L) — the number of the main transport document for the whole shipment. What this document is — in our article on the bill of lading.
- Booking number — the number of the vessel space reservation, assigned by the line when the shipment is confirmed.
Any of them works for tracking on the line's website, but the container or B/L number is the most convenient. These numbers are given to you by the seller or the freight forwarder after loading.
Method 1. The shipping line website
The most accurate source is the website of the shipping line carrying your container. The data there is primary and updates in real time. You need to know the name of the line (it is stated in the bill of lading) and enter the container or B/L number in the Track / Tracking field. Below are the tracking pages of the world's seven largest lines:
- MSC — msc.com/en/track-a-shipment
- Maersk — maersk.com/tracking
- CMA CGM — cma-cgm.com/ebusiness/tracking
- COSCO — elines.coscoshipping.com/ebusiness/cargoTracking
- Hapag-Lloyd — hapag-lloyd.com/en/online-business/track
- ONE (Ocean Network Express) — ecomm.one-line.com — Cargo Tracking
- Evergreen — ct.shipmentlink.com — Cargo Tracking (the ShipmentLink system by Evergreen)
Which line carries your cargo is always stated in the bill of lading and in the booking confirmation. Who these carriers are and what their fleet is like — we wrote in our guide to sea container shipping.
Method 2. Universal tracking services
If you do not know which line is carrying the container, or you are tracking several shipments from different carriers at once, aggregator services are convenient. You enter the container number and the service itself identifies the line and pulls the status. Popular ones: Track-Trace, SeaRates, VesselFinder, MarineTraffic (the last two also show the vessel on a live map by its name or IMO number). The downside of aggregators is that the data comes with a delay and is sometimes incomplete, so for critical cargo cross-check with the line's website.
Method 3. Through a freight forwarder
The simplest way is to hand the monitoring over to a freight forwarder. They track the vessel, see transshipments and delays, know the ETA in advance and warn about demurrage risks. Trans-Hope handles every container from departure from the Chinese port to arrival in Ukraine and reports the status to the client at the key stages — the delivery is organised by the sea container shipping service.
Statuses and abbreviations in tracking: ETA, ETD, POL, POD
In the line's tracking you will see a set of abbreviations. Here are the main ones:
| Abbreviation | Full name | What it means |
|---|---|---|
| ETD | Estimated Time of Departure | the estimated departure date |
| ETA | Estimated Time of Arrival | the estimated arrival date |
| ATD | Actual Time of Departure | the actual departure date |
| ATA | Actual Time of Arrival | the actual arrival date |
| POL | Port of Loading | the port of loading |
| POD | Port of Discharge | the port of discharge |
| Gate in / Gate out | — | the container entering / leaving the terminal |
| Empty return | — | return of the empty container to the line |
Most often the client cares about the ETA — the estimated date of arrival at the destination port. It is from this date that document preparation and customs clearance are counted back.
What rolling is and why a container gets stuck
Sometimes the tracking shows that the container did not leave on the scheduled sailing. This is rolling — moving the container to the next vessel. The reasons: vessel overbooking, a weight imbalance, a missed loading window, and less often non-payment or document problems. Rolling pushes the ETA back by days or weeks. If you see the status not changing for a long time, it is a reason to ask the line or forwarder for the current sailing and the new date.
How a container number is structured (ISO 6346)
The container number is standardized (ISO 6346) and consists of 11 characters: 4 letters + 7 digits. The first three letters are the owner code (prefix), the fourth letter U marks a freight container. Then come 6 digits of the serial number and one check digit, by which you can verify that the number has been entered without error. Example: MSCU 123456 7. If the tracking “cannot find” the container, the first thing to check is that the number is entered exactly, with no missing characters.
Common mistakes when tracking a container
- Searching on the wrong line — first check the carrier's name in the bill of lading.
- Entering the number with an error or extra spaces — check the check digit.
- Relying only on an aggregator — for important cargo cross-check with the line's website.
- Ignoring transshipment at a hub (Constanta, Gdansk) — on the transit leg the status updates less often.
- Forgetting about free time — you track not out of curiosity but to be in time with documents and avoid demurrage.
Which number should I track a container by?
