What is container per diem, and when does the clock stop?
Per diem is the common name for the ocean line's detention charge. Its clock stops when the empty is accepted back at the ramp or at a depot your line names. It starts when your container leaves CN Brampton or CPKC Vaughan. How you unload, and how fast the empty goes back, decide how long it runs.
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What is per diem on a container?
Per diem is the ocean line's charge for keeping its container past free time after it leaves the ramp. It is not railway storage, and it is not demurrage. Each of the three runs on its own clock.
Storage at the ramp
The railway bills storage when the container sits at its ramp past free time. Free time at the ramp is short and set by the railway's tariff, and the clock can keep running on weekends.
Demurrage
The line bills demurrage while its container is still at the ramp after the line's own free time. It is a separate bill from railway storage.
Per diem
Once the container leaves the ramp, the line bills detention, often called per diem, until the empty is returned.
The two charges at the ramp are explained in storage, demurrage and per diem. The words on the paperwork are defined in drayage terms in plain English.
When does per diem start?
Per diem starts when the container leaves the ramp. Leaving CN Brampton or CPKC Vaughan generally stops the line's demurrage and starts its per diem.
The gate out is the hand-off. Before it, railway storage and line demurrage can build. After it, per diem runs until the empty is back.
Pulling a container early does not make the time free. It moves days from the ramp clocks to the per diem clock.
- At the ramp: storage and demurrage
- After the gate: per diem
- Empty accepted back: the clock stops
The railway's last free day and the line's per diem free time are separate. Ask for both.
When does the per diem clock stop?
It stops when the empty is accepted back at the place your line names. That is the ramp it came from, or a depot named in the line's return instructions.
Gate out
The container leaves CN Brampton or CPKC Vaughan. Per diem starts.
Delivered
Live unload with the driver waiting, or a drop if you have the yard space.
Unloaded
The container is empty, but the clock keeps running until it is back.
Empty accepted back
We return it to the ramp or the depot the line names. Per diem stops here.
A return that is refused, late or sent to the wrong place keeps the clock running. Ask the line to confirm the return date it recorded, because that date ends per diem. Where empties go: empty container returns in the GTA.
Who sets the per diem free time, and does it count weekends?
Your ocean line sets it, and your contract with the line can differ from its public terms. Some lines count working days only, others count every day.
This page gives no number of free days, because each line and each contract sets its own. Ask the line, or the forwarder who booked the freight.
Not every container belongs to an ocean line. When a railway supplies the container, its own tariff sets the detention. CPKC's Intermodal Services Tariff, effective October 2, 2026, charges detention on CPKC's own equipment and storage on other containers at its terminals.
- The per diem free time
- Working days or every day
- Where the empty goes back
Does live unload or drop change per diem?
Yes. A live unload sends the empty back in the same visit, so per diem usually stops sooner. A drop lets you unload on your own time, but per diem runs until the empty is back.
Live unload. The driver waits at your dock while you unload, then takes the empty straight back. Have the door and crew ready: time past the free time on the rate confirmation is billed as waiting time.
Drop. If you have the yard space, we leave the container on a chassis at your site. We come back for the empty when you are done, so tell dispatch as soon as it is empty.
Tell us which at tender. How to choose for your dock: live unload or drop.
- Live unload: empty back sooner
- Live unload: dock ready on arrival
- Drop: unload on your own time
- Drop: per diem keeps running
How do you keep per diem down?
Shorten the time between the gate out and the empty return. Most of that time is decided before the truck reaches the ramp.
Releases before arrival
Ask your customs broker and your line to have both releases in place before the container reaches the ramp.
Book the pickup early
Send us the container number and your receiving hours when the arrival notice comes in. We book the pickup at the ramp.
Unload promptly
Choose a live unload when your crew can unload while the driver waits. On a drop, unload and call dispatch.
Return details at tender
Send the line's return instructions with the tender, so the empty goes to the right place the first time.
Dock not ready before the last free day? A pre-pull takes the container off the ramp early. It trades ramp storage and demurrage for extra per diem days. Read when a pre-pull pays.
What does Setara Transport do?
Our truck moves start and stop the per diem clock: the ramp pull, the delivery and the empty return. We do not set per diem. Your ocean line does.
- The container number and the ramp
- The line's last free day and per diem free time
- The line's return instructions for the empty
- The delivery address and receiving hours
- Live unload or drop at your dock
- The cargo weight in each container
- Check the releases and holds before a truck goes out
- Book the pickup at the ramp: the CN Brampton gate appointment or the CPKC Vaughan pickup
- Pull the container on our own chassis
- Deliver across the GTA and Ontario, live unload or drop
- Bring the empty back to the ramp or the depot the line names
Send us the container number and we tell you what is still missing. Per diem charged by the line is for the account of the party responsible under the rate confirmation. Where a delay is ours, we own it. The rule is in our conditions of carriage.
Per diem questions.
Is per diem the same as detention?
When does per diem start and stop?
What is the difference between demurrage and per diem?
Does per diem run on weekends?
Does a drop cost more per diem than a live unload?
More answers for importers.
Storage and demurrage at the ramp
The two clocks before the container leavesWhere do I return an empty container?
Where the empty goes and what to send dispatchLive unload or drop?
Which delivery fits your dockCan storage or demurrage be waived?
Who pays when the delay was not yoursWhat goes into a drayage rate?
The lines on the rate confirmation, with no pricesAll answers
Every answer for importers and forwardersContainer leaving the ramp soon? Send us the number.
The container number, the ramp, the last free day and where the empty goes back.