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Why two sites show two different ETAs for the same container

Both can be right. They are usually measuring different things, and one of them is older than it looks.

Ethan Davies · 5 min read

Quick take

  • Vessel ETA and container ETA are not the same number.
  • Berthing, arrival and discharge are three separate events.
  • A cached figure that never moves is worse than a figure that moves often.

Two screens, two dates, same container. This comes up constantly and it makes people distrust both sources. Usually neither is lying.

Three numbers people call ETA

  • Vessel ETA. When the ship expects to reach the port area.
  • Berthing time. When it actually gets a berth, which depends on congestion and can be a day or more later.
  • Container discharge. When your specific container comes off, which depends on where it sits in the stow.

A site quoting vessel ETA and a site quoting discharge estimate will disagree, and both are technically correct.

The stale data problem

The more common cause is age. Schedules change constantly. A source that refreshed six hours ago and one that refreshed six days ago will show different numbers, and there is often nothing on screen telling you which is which.

This is why an ETA that has not moved in three weeks should worry you more than one that moves every other day. A moving figure is a live figure.

See it on your own shipment

Paste a container number, bill of lading or booking reference. We detect the carrier across 170+ shipping lines, and when the data does not line up, a person checks it.

Which one to quote

Give your customer the discharge estimate, and label it. Saying the vessel arrives Tuesday when the container will not be available until Thursday creates a problem you will own. Add the date the estimate was last refreshed if your tool shows it. That one habit removes most of the arguments.

Questions people ask

Which ETA should I give my customer?

Quote the discharge estimate and say what it is. Vessel arrival is not when your cargo becomes available.

Why does the ETA move every day?

Because it reflects real conditions. Weather, congestion and berth availability all shift arrival by hours or days.

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