Demurrage and Detention: The Import Costs Nobody Warns You About

Ask most first-time importers about demurrage and detention and you'll get a blank stare. Ask them again after their first significant shipment delay and you'll get a very different reaction — usually involving a specific dollar amount they wish they had never seen on an invoice.

These two charges are among the most expensive and least understood costs in import logistics. Understanding them before you need to isn't optional if you want to run profitable import operations.

Demurrage vs. Detention: The Core Distinction

The terms are often used interchangeably, which creates confusion. They're related but distinct charges.

Demurrage is the charge for keeping a shipping container at the port terminal beyond the "free days" allotted by the shipping line. The clock runs from when the container is discharged from the vessel until it's picked up from the terminal. If the carrier gives you 5 free days and you don't pick up the container on day 6, demurrage starts accruing.

Detention is the charge for keeping the container beyond the free time once it has left the terminal. You've picked up the container, but the shipping line expects it returned within a set period (typically 5-7 days). If your goods take longer to unload, or if a logistics problem delays the empty container return, detention charges accumulate.

In short: demurrage is about the container sitting at the port. Detention is about you keeping the container after pickup. Both are charged by the day and both can escalate quickly.

What Triggers These Charges

Importers get hit with demurrage and detention from predictable sources:

Customs Holds

When customs selects your shipment for examination, processing can take days. Free time keeps running. Customs doesn't care about your carrier's free day allowance, and the carrier doesn't care that customs is holding your container. The clock runs regardless.

Document Problems

Missing or incorrect documents — especially the original Bill of Lading, which must typically be surrendered to release the container — can hold up pickup while free time expires. A courier delay on a physical Bill of Lading has caused importers thousands of dollars in demurrage on otherwise problem-free shipments.

Port Congestion

During periods of port congestion (which have become more frequent and severe in recent years), appointments for container pickup can be unavailable, or scheduled pickups get cancelled due to terminal operating issues. The shipping line's position: that's not our problem.

Warehouse and Logistics Delays

If your consignee warehouse isn't ready to receive the goods, or if your drayage carrier has capacity problems, the container sits. Once it's been picked up, every extra day triggers detention.

How Much Do These Charges Cost?

Rates vary significantly by carrier, port, and container type. As a rough benchmark in major US ports:

• Demurrage typically starts at $75-$150 per container per day for the first few days, escalating to $200-$450 per day after a week
• Detention rates are typically $100-$200 per day for standard containers
• Refrigerated containers carry significantly higher rates

A container stuck in customs examination for 10 days, followed by a 5-day detention overage, can generate $3,000-$6,000 in charges on a single container. On a multiple-container shipment during port congestion, these charges can exceed the value of the goods.

Strategies to Minimize Exposure

Understand Your Free Time Before the Shipment Arrives

Know exactly how many free days you have from the carrier and terminal before your vessel arrives. Calendar them. Build your pickup logistics plan around that window, not around when it would be convenient to pick up the cargo.

Prioritize Document Readiness

All customs entry documents, the original Bill of Lading (or telex release), and any required permits or certifications should be fully prepared before the vessel arrives. Document problems that emerge after arrival eat directly into free time.

Have a Backup Drayage Option

If your primary drayage carrier can't pick up the container when scheduled, you need an alternative. The cost of maintaining two carrier relationships is trivial compared to the cost of one missed pickup during peak congestion.

Negotiate Free Time Upfront

On high-volume trade lanes or with high-volume carriers, free time is negotiable. If you're moving consistent volume, ask your freight forwarder to negotiate extended free time as part of the carrier arrangement. Three extra free days on every container is worth negotiating for.

Watch for Congestion Signals Early

Port congestion doesn't appear overnight. Dwell times at major ports are published and tracked. If congestion is building at your destination port weeks before your vessel arrives, that's the time to accelerate document preparation and drayage scheduling — not after arrival when the terminal is backed up.

When to Fight a Charge

Not all demurrage and detention invoices are correct. Carriers make billing errors. Free time calculations can be disputed if the vessel arrived late and the free time clock should start later. Charges that accrued during force majeure events (port strikes, for example) are sometimes waiveable.

Document everything: when the vessel arrived, when you received the cargo release, when you scheduled pickup, why any delays occurred, and what communications you had with the carrier and terminal. A well-documented dispute has a much higher chance of getting a waiver or reduction than an undocumented complaint.

Demurrage and detention are facts of import logistics. The importers who control these costs are the ones who plan for them proactively — not the ones who discover them on the invoice after the fact.