Demurrage and Detention Charges Explained: Japan Ocean Freight

01Two Charges, Two Different Triggers

It’s easy to lump demurrage and detention together — both are late fees tied to a container — but they cover different periods and different things.

The U.S. Federal Maritime Commission’s overview of demurrage and detention draws the same line: demurrage tracks container time at the marine terminal, while detention tracks the container once it’s out with the customer. Put simply, demurrage penalizes a slow pickup, and detention penalizes a slow return. On congested routes, a shipment can run into both, one after the other.

Some ports also levy their own storage fee separately from the carrier’s demurrage charge, so it’s worth checking whether that applies at your discharge port before cargo arrives.

02How Free Time Is Actually Counted

Every carrier and contract sets its own free-time allowance — there’s no industry-standard number of days you can assume applies to your shipment. Confirm the actual allowance for your specific booking rather than relying on what worked on a previous shipment or a different trade lane.

Where the clock starts differs too. Some carriers count from the vessel’s arrival date, others from when discharge is completed. That starting point determines how much runway you actually have, so it’s worth confirming rather than assuming.

Whether weekends and public holidays count toward free time also varies by carrier. A nominal allowance can mean very different real-world coverage depending on whether it’s calendar days or working days.

Overage charges typically escalate the longer a container sits — the per-diem rate climbs in tiers the further past free time you go. A short delay can turn into a disproportionate bill quickly, which is why early pickup is consistently the cheaper option, even when it means paying for warehouse space sooner than planned.

03How to Keep These Charges Off Your Invoice

Three habits do most of the work in practice.

Get paperwork sorted before the vessel arrives. Document problems on the import side are the single most common reason pickup gets delayed. Confirm that the B/L details match the actual cargo before the ship even sails, so nothing surfaces as a surprise at destination.

Confirm your consignee can actually receive the cargo. A full warehouse or a shortage of devanning labor at destination delays pickup just as often as paperwork issues do. Check receiving capacity before the container lands, not after.

Build in extra time at congested destinations. At ports with chronic congestion, it’s sometimes possible to negotiate an extended free-time allowance in advance — worth raising with your forwarder before the shipment departs, rather than after the clock has already started.

For inland destinations with no convenient point to return an empty container, arranging an SOC (Shipper-Owned Container) removes detention risk entirely, because there’s no return obligation to miss. Demurrage can still apply if pickup from the terminal itself is delayed, so early collection still matters either way.

FAQFrequently Asked Questions