The most expensive lines on an import invoice usually aren’t rates at all. They’re meters — demurrage and detention — and they run on the calendar, not the map. You can negotiate a great ocean rate and hand it all back in demurrage on a box that sat three days too long. The good news: these clocks are predictable, and predictable clocks can be beaten.
Two clocks, not one
People blur them together; they’re different meters on different equipment in different places.
- Demurrage runs while the container sits inside the terminal past its free time. It’s the port’s charge for the box occupying their yard.
- Detention runs while the container sits outside the terminal — at your dock or the trucker’s yard — past its free time. It’s the carrier’s charge for their equipment being held.
There’s a third, related meter: per-diem on the chassis, if you’re holding that too. The point is that from the moment a box is available to the moment the empty is back, something is metered — the job is to keep every meter short.
What starts each clock
- Demurrage starts when the container is discharged and available for pickup, and free time runs out. Your deadline is the last free day (LFD).
- Detention starts when you take the box out and free time on it runs out — the return-by date.
Weekends and holidays usually still count. And critically, a customs hold or a missing appointment doesn’t pause demurrage — the clock runs even when the delay isn’t yours to fix.
The moves that stop them
Beating the clocks is operational, not clever. In rough order of leverage:
- Know the LFD before the vessel arrives. You can’t beat a deadline you’re tracking after the fact. Every import move should start from its last free day.
- Clear customs early. File the entry so release lines up with discharge — a box that’s cleared can move the moment it’s available. A customs hold is the most common cause of demurrage.
- Pre-pull when the window is tight. Pulling the box to the trucker’s yard before the LFD stops demurrage cold; a day of yard storage is far cheaper than escalating demurrage.
- Match delivery to your dock’s real speed. If you can’t unload fast, drop-and-hook instead of making a driver wait — but then watch the detention clock on the held box and return the empty promptly.
- Return empties on time. Detention and per-diem only stop when the equipment goes back. Plan the return, don’t let it drift.
Why “just negotiate the fee” doesn’t work
Shippers often try to argue demurrage down after it’s incurred. It rarely moves, because the charge reflects real yard occupancy and escalates by design to force boxes out. The leverage is before the clock, not after: dispatch speed, early clearance, and a pre-pull on a tight window save more than any after-the-fact negotiation.
The one-line version
Demurrage and detention are time, not distance — so they’re won with tracking and dispatch, not with rate-shopping. Track the last free day, clear early, pre-pull when it’s tight, and return empties fast. We run every import move against its free-time clock from day one; hand us a shipment and we’ll keep the meters short.