Free Detention Calculator — Know Your Free Days Before They Expire
Compare container return deadlines and detention penalties across Maersk, MSC, CMA CGM, Hapag-Lloyd, ONE, Evergreen, Yang Ming, and ZIM — before your free time runs out.
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Understanding Detention: The Hidden Cost After Pickup
While most shippers focus on freight rates when choosing a carrier, detention charges represent one of the largest hidden costs in container shipping. Detention fees apply from the moment you pick up the container at the port until you return the empty container to the designated depot. In 2026, with supply chain disruptions causing chassis shortages and warehouse backlogs, detention costs have surged to record levels across many trade lanes.
The difference between carriers on a single route can be staggering. One carrier might offer 7 free days for detention while another offers only 4. With daily rates of $100 or more after free time expires, choosing the wrong carrier can add $300 to $700 in unnecessary fees per container — money that goes straight to the bottom line.
See the ShippingRates methodology for the validation process behind carrier-backed detention and D&D data.
Detention vs. Demurrage: Know the Difference
These two charges are frequently confused, but they cover different stages of the container journey:
- Demurrage covers the time a loaded container sits at the port terminal before you pick it up. The clock starts when the container is discharged from the vessel.
- Detention covers the time the container is in your possession outside the terminal. The clock starts when you gate out the container and stops when you return the empty to the designated depot.
- Combined D&D — some carriers merge both into a single allowance (common in European ports), while others keep them strictly separate with independent free-day pools.
Both charges can stack on the same shipment. If you are late picking up your container (demurrage) and then late returning it (detention), you could face penalties at both ends. Our demurrage calculator covers the port-side charges, while this page focuses on the post-pickup detention side.
Regional Detention Differences
Detention policies vary dramatically by region, and understanding these differences is critical when routing cargo through unfamiliar ports:
- United States: The FMC requires carriers to provide reasonable free time and prohibits charges when delays are outside the shipper's control. Standard free days are 4 to 7 for dry containers.
- Europe: Many carriers offer combined D&D allowances of 10 to 14 days. The EU has been tightening regulations, but enforcement varies by country.
- Asia: Free-day policies are often more generous (7 to 10 days in major ports like Shanghai and Singapore), but off-dock depots can be far from the port, adding trucking time to your return window.
- Africa and South America: Shorter free days (3 to 5 in many ports) combined with slower customs clearance make these regions particularly high-risk for detention charges.
How to Calculate Your Total Container Cost
Detention is just one component of the total landed cost of a container shipment. To get the full picture, you need to factor in the freight rate, demurrage risk, detention risk, local charges, inland haulage, and any surcharges like the EU ETS carbon levy. Our True Cost of Shipping a Container guide breaks down all of these components with real 2026 numbers.
Frequently Asked Questions
What is detention in container shipping?
Detention is a charge applied by the shipping line when an importer or consignee holds a container outside the port terminal beyond the allowed free period for return. Once you pick up the container from the port, the clock starts. If you do not return the empty container to the designated depot before the free time expires, daily detention fees begin to accrue. Detention charges are separate from demurrage and apply to the period the container is in your possession.
How is detention different from demurrage?
The key distinction is location. Demurrage is charged while the container sits at the port terminal before you pick it up. Detention is charged after the container leaves the terminal and is in your possession. Think of demurrage as a port storage fee and detention as an equipment usage fee. Both have separate free-day allowances and separate rate schedules, and they can overlap on the same shipment if you are slow at both ends.
What are typical detention free days and rates?
Standard tariff detention free days typically range from 4 to 7 days in most regions, though contracted shippers may negotiate 10 to 14 days. After free time expires, rates usually start at $50 to $100 per day for dry containers and escalate to $150 to $250 per day after the first week. Reefer containers have significantly higher detention rates, often starting at $150 per day, because the carrier loses revenue while the refrigerated unit is out of service.
What are the FMC rules on detention charges?
Under FMC Interpretive Rule 545, detention charges in the US must serve as an incentive to return containers promptly, not as a revenue-generating mechanism. Carriers must provide a clear, accessible schedule of charges. Detention cannot accrue when the delay is caused by factors outside the shipper's control, such as when the designated return depot is closed or full. The FMC also requires carriers to offer a reasonable dispute resolution process for contested detention invoices.
How can I avoid detention charges?
Plan your unloading and container return schedule before the container arrives. Key strategies include: arranging a chassis and driver in advance, scheduling warehouse receiving windows to match container pickup, stripping the container as quickly as possible (ideally same day or next day), confirming the return depot location and operating hours before dispatching, and using our detention calculator to compare carrier policies and choose the one with the most generous terms for your route.