What Is Demurrage in Shipping? Everything You Need to Know

Demurrage is a charge levied by shipping lines when a container remains at the port terminal beyond the allotted free time after it has been discharged from the vessel. It is one of the most common — and most avoidable — additional costs in ocean freight.

How demurrage works

When a container is unloaded from a vessel, the carrier grants a fixed number of "free days" during which the container can remain at the terminal without charge. This free time typically ranges from 3 to 7 days depending on the carrier, the port, the trade lane, and whether you've negotiated additional free time in your contract.

Once free time expires, demurrage charges begin accruing on a per-day, per-container basis. Rates escalate the longer the container sits — the first few days might cost $75-150 per day, but after a week or more, rates can climb to $300-400+ per day. Reefer containers are almost always charged at higher rates due to the power consumption and equipment scarcity.

Demurrage vs detention: what's the difference

These terms are often confused. Demurrage applies while the container is at the port terminal — it's essentially rent for the terminal space. Detention applies after the container has left the port — it's rent for the container itself, measured from the time it leaves the terminal gate until the empty is returned to the carrier's depot.

Some carriers combine these into a single "demurrage and detention" charge with a unified free time window. Others keep them separate, each with their own clock and tariff. Understanding your specific carrier's terms is essential for managing costs.

What triggers demurrage

The demurrage clock starts at discharge — the moment the container is physically unloaded from the vessel onto the terminal yard. Several factors can prevent timely collection: customs clearance delays are the most common cause, where documentation issues, inspections, or regulatory holds prevent release. Carrier or terminal holds may block collection even after customs clearance — these might be freight payment disputes, missing documentation, or operational restrictions. Haulier availability problems, particularly during peak periods, mean the truck isn't available to collect within the free time window. And simple lack of awareness remains a major factor — teams don't realise free time is expiring because they're not tracking discharge dates in real time.

How to calculate demurrage charges

Demurrage is calculated as: (number of days beyond free time) × (daily tariff rate) × (number of containers).

For example, if your free time is 5 days and your container is collected on day 8, that's 3 days of demurrage. If the rate is $200/day, the charge is $600.

However, the calculation is rarely this simple in practice. Tariff rates often escalate in tiers (days 1-3 at $100, days 4-7 at $200, days 8+ at $350). Weekends and holidays may or may not count depending on the port and carrier. And some ports apply demurrage from the date the container is made available for collection rather than the discharge date — which matters when the container is under hold.

How much does demurrage cost?

Rates vary dramatically by port, carrier, and container type. As a rough guide for 2026, standard dry containers typically incur $75-400 per day depending on the port and the duration of overstay. Reefer containers are typically 1.5-2x the standard rate due to electricity and equipment costs. High-demand ports like Rotterdam, Felixstowe, Los Angeles, and Singapore tend to have higher tariffs than smaller regional ports.

For a shipper handling 50-100 containers per month, even a modest demurrage incidence rate of 8-12% can translate to $10,000-50,000+ in annual avoidable costs.

How to avoid demurrage charges

The most effective demurrage prevention strategy is simple in concept: know your deadlines and act before they pass. In practice, this requires real-time tracking of discharge dates and free time countdowns, predictive ETAs that give you enough lead time to prepare customs documentation and arrange haulage, automated alerts at critical thresholds (50% free time elapsed, 24 hours remaining, free time expired), and a fast communication chain so that when a container is at risk, the right people are notified and can act immediately.

The difference between companies that pay significant demurrage and those that don't isn't the size of their logistics team — it's the quality of their information and the speed of their response.

How to dispute demurrage charges

Not every demurrage invoice is accurate. Common errors include charges for days the container was under customs or port hold (where the delay is not the shipper's fault), incorrect free time calculations (the wrong free time allowance applied), wrong tariff rates (standard rates applied instead of contracted rates), and charges beginning before the container was actually available for collection.

If you're tracking the actual milestones — discharge date, hold periods, availability date, collection date — you have the data to verify every line item on a demurrage invoice. Industry analysis suggests that up to 25% of ocean freight invoices contain refundable errors. For demurrage specifically, the error rate can be even higher because the calculations involve multiple date comparisons, tariff lookups, and hold period exclusions.

To dispute, you need to document the discrepancy clearly, reference the applicable tariff or contract terms, and submit the dispute to the carrier within their specified timeframe. Having the tracking data to support your case makes the difference between a dispute that gets resolved quickly and one that gets rejected.