See any China United Lines shipment through four independent lenses: carrier events, live vessel position, schedule and a forecast ETA. Not one source that can be wrong.
The fastest way to track a China United Lines container is to enter your container, bill of lading, or booking number at trackingmcp.com/track/china-united-lines. You see China United Lines's carrier events, live vessel position, forecast ETA, and demurrage & detention free days together; DCSA-normalised across 234+ ocean lines, without a China United Lines account.
China United Lines containers begin with CULU. Bill of lading and booking numbers work too.
China United Lines (CULines), founded 2005 in Shanghai by the Unitrans Group, an intra-Asia and cross-strait container carrier now reaching to the Middle East and Europe.
Worth knowing Cut its teeth on the Taiwan cross-strait trade before expanding into deep-sea lanes during the 2020s box boom.
Actuals Carrier events: Milestones from the carrier.
Position Satellite · AIS: Where the ship is, live.
Plan Carrier schedule: The line’s committed plan.
Probability ETA forecast: A cross-checked forecast.
China United Lines schedule reliability: measured, not marketed
81 arrivals · 7 lanes · 12 mo
On-time · ±24h
33.3%
vs fleet median 43.7%
Delay when late
59.9h
median · fleet 59.1h
Sample
81
tracked arrivals · 7 lanes
China United Linesfleet median (21 carriers)
Measured across 81 tracked arrivals on 7 trade lanes over the past 12 months, China United Lines vessels arrived within 24 hours of schedule 33.3% of the time, with a typical delay of 2.5 days (59.9 hours) when late. These are TrackingMCP's own measurements from actual arrivals against the published schedule, refreshed as new arrivals land. See how every carrier compares on the Carrier Reliability Index →
How to track a China United Lines shipment
4 steps
Find your China United Lines reference. Locate your China United Lines container number, bill of lading, or booking number; it is on your booking confirmation, arrival notice, or commercial invoice.
Enter it at trackingmcp.com/track/china-united-lines. Paste the reference into the search box. TrackingMCP auto-detects whether it is a container, bill of lading, or booking number and resolves it to China United Lines.
Read the live, cross-checked status. See China United Lines's own milestones, the vessel's live AIS position, the published schedule, and a forecast ETA side by side, so one stale source cannot mislead you.
Watch the demurrage & detention clock. Track the free-time countdown and get an alert before China United Lines demurrage or detention charges begin to accrue.
What you'll see when tracking China United Lines
DCSA model
Every China United Lines shipment is normalised to the DCSA Track & Trace model, so the milestones read the same as any other carrier:
Gate-inThe empty or full container enters the origin terminal or depot.
LoadedThe container is loaded onto the ocean vessel.
Vessel departureThe ship sails from the load port (the free-time clock has not started yet).
TransshipmentOn indirect routings, the box is discharged and reloaded at a hub port.
Arrival & dischargeThe vessel arrives at the destination port and the container is discharged; this is when import demurrage free time starts.
Gate-out / deliveredThe container leaves the terminal for delivery; detention free time runs until you return it empty.
China United Lines demurrage & detention free time
free-time clock
Every China United Lines import container has a free-time clock: the calendar days before demurrage (box left in the terminal) or detention (box kept out too long) charges start. Look up China United Lines's published free days by country on the free-time reference →, and TrackingMCP alerts you before the clock runs out.
China United Lines container number format, and the mistakes that break tracking
ISO 6346
A China United Lines container number follows ISO 6346: four letters, six digits, then a check digit: for example CULU 123456 7. The first three letters identify the owner (CULU), the fourth is the equipment category (usually U).
Letter O vs zeroThe classic. Container numbers never contain the letter O in the digit positions. If tracking returns nothing, check character 5 onwards.
Spaces and hyphensFine either way; TrackingMCP strips them. But a missing final check digit makes the number unresolvable.
B/L pasted as a container numberBills of lading have a different shape (often starting CULU). Paste it as-is and the format is auto-detected.
Wrong check digitOne mistyped digit fails silently on many carrier sites. Validate any number with the free ISO 6346 check-digit calculator →
China United Lines tracking statuses that confuse people
5 answers
RolledYour container missed its planned vessel; usually overbooking or a schedule change, and is rebooked onto a later sailing. The new ETD/ETA shows once the carrier assigns the next vessel.
Transshipment in progressThe box was discharged at an intermediate hub and is waiting for its connecting vessel. Days without a new event here are normal; hubs often move a box only when the connection arrives.
Discharged vs. availableDischarged means the crane took the box off the ship; available means the terminal has released it for pickup after unstacking, customs and fee clearance. The gap is typically hours to a few days.
Customs or carrier holdThe container is physically at the terminal but blocked from release; customs inspection, unpaid charges, or missing documents. Tracking looks "stuck" until the hold clears.
Empty returnedThe importer has returned the empty box to the depot; the shipment cycle is complete and this is the final event on most timelines.
China United Lines tracking not updating? Six reasons
6 reasons
Carrier events lag at origin. China United Lines's own systems often post the first events 24–48 hours after gate-in or loading. If your booking is fresh, the timeline fills in as the carrier's data catches up.
The box is on a feeder or transshipment leg. Between discharge at a hub and loading onto the connecting vessel, many carriers publish nothing. The live vessel position keeps moving on TrackingMCP even when China United Lines's milestones pause.
Wrong reference type. A booking number can stop updating once the carrier splits it into containers. Track by container number for the fullest history; TrackingMCP auto-detects which type you pasted.
The shipment is too new. A booking confirmed today may not be in China United Lines's public tracking yet. It usually appears within a day of the carrier issuing the booking confirmation.
Mid-ocean quiet stretch. On a long leg there are simply no port events to report. Satellite AIS position and the forecast ETA still update daily; milestones resume at the next port call.
A typo in the reference. One wrong character (the letter O vs zero is the classic) returns an empty or stale record. Validate the number with the free ISO 6346 check-digit calculator.
Carrier reference facts last reviewed July 2026.
China United Lines tracking FAQ
7 questions
How do I track a China United Lines shipment?
Enter your China United Lines container number, bill of lading, or booking reference in the search box above. TrackingMCP auto-detects the format and returns live carrier events, the vessel's AIS position, and a forecast ETA. Your first shipment is free, no account needed to start.
What is China United Lines's SCAC code?
China United Lines's SCAC (Standard Carrier Alpha Code) is CULU. TrackingMCP uses it to route your reference to the right carrier automatically.
What do China United Lines container numbers look like?
China United Lines containers follow the ISO 6346 standard; four letters then seven digits; beginning with prefixes such as CULU.
How accurate is China United Lines tracking?
Every China United Lines shipment is cross-checked across four independent sources; the carrier's own events, live AIS vessel position, the published schedule, and a forecast ETA, so one stale or wrong source can't mislead you.
Why is my China United Lines tracking not updating?
Usually one of: China United Lines posts events 24–48h behind reality at origin, the box is between vessels at a transshipment hub, the shipment is too new to be in the system, or there's a typo in the reference. TrackingMCP cross-checks the live vessel position and schedule, so you still see movement while carrier milestones pause.
How reliable are China United Lines's schedules?
On the lanes TrackingMCP measures, China United Lines arrived on schedule 33.3% of the time across 81 tracked arrivals (7 lanes, trailing 12 months); the typical delay when late was 2.5 days (59.9 hours). That's measured from actual arrivals vs. the published schedule, not a marketing figure.
Which trade lanes does China United Lines serve?
China United Lines serves Intra-Asia, Middle East, North Europe, Indian subcontinent. TrackingMCP tracks China United Lines shipments across all of them.