Yard dwell time is the interval between a vehicle passing your gate and that same vehicle leaving it. Everything that happens in between belongs to you, not to the carrier, and that is why it is the number a site is judged on when carriers reprice a lane.
Most European sites cannot state their dwell figure. They can state their appointment adherence and their detention invoices, which are downstream of it. This guide covers where dwell starts and stops, how to measure it with data you already generate, the four causes worth attacking, and how dwell relates to detention, which is the charge it eventually turns into.
Where dwell starts and where it stops
Dwell starts at gate-in and ends at gate-out. That definition sounds obvious and is where most measurement projects go wrong, because sites quietly measure something narrower: dock occupancy, or the time from dock assignment to departure. Both exclude the queue, which is usually the largest single block of time on site.
Split the total into four intervals and you can act on it:
- Gate to yard position. Check-in, paperwork and being told where to go.
- Yard position to dock. Waiting for a door, plus the spotting move if the trailer is dropped.
- Dock to load complete. The only interval most warehouses actually track.
- Load complete to gate-out. Paperwork, seals and the exit queue.
A site with a good loading time and a terrible dwell figure has its problem in intervals one, two and four. That is the common case, and it is invisible to a warehouse management system because none of it happens inside the four walls.
How to measure dwell without buying hardware
You do not need cameras or RFID to start. Three timestamps give you a usable baseline: the booked slot, the actual arrival and the departure. The first comes from your booking system, the second and third from the gate log.
Measure three things and nothing else in month one:
- Median dwell, not mean. One truck stuck for nine hours will drag an average into meaninglessness. The median tells you what a normal driver experiences.
- The 90th percentile. This is the number carriers price against, because it is the risk they are underwriting when they quote your lane.
- Dwell by hour of arrival. This single cut usually explains most of the problem before you investigate anything else.
If your gate log lives on paper, that last cut is still worth an afternoon of manual entry. Sites that do it almost always find the same shape: a spike in the first two hours of the shift, caused by everyone being told to arrive early.
The four causes worth attacking
Arrival clustering
When arrivals are not spread across the shift, the yard absorbs the difference. This is the cheapest cause to fix because it needs no equipment, only enforced booking windows. It is what dock scheduling software exists to do, and the practices that make it stick are in our guide to dock scheduling best practices.
Unassigned trailers
A dropped trailer with no known position and no move order is dwell accumulating silently. Nobody is waiting for it, so nobody reports it, and it surfaces weeks later as an aged trailer nobody can account for. This is what yard management software addresses.
Spotting sequence
Yard moves executed in the order they were requested rather than in the order doors will free means the spotter is busy while the dock is idle. The move queue has to be driven by the dock plan, not by the radio.
Exit friction
Paperwork, seal checks and a single exit lane can add thirty minutes after the load is finished. It is the least glamorous interval and often the easiest to halve, because electronic documentation removes most of it. See eCMR software for how the consignment note moves off paper.
Dwell and detention are not the same number
Dwell is operational. Detention is contractual: the charge that starts once free time expires. Free time is typically two hours in European road freight, so a site with a median dwell of one hour and a 90th percentile of four hours has an operational problem in the tail and a financial problem in the same place.
This is why the median alone is a misleading target. Cutting median dwell from 90 to 75 minutes changes almost nothing on the invoice if the tail is untouched. Cutting the 90th percentile from four hours to two removes the charge entirely. The full mechanics of the charge, including who pays and what evidence holds up in a dispute, are covered in our guide to detention and demurrage in road freight, and you can size your current exposure with the detention cost calculator.
What a realistic target looks like
Sites that book slots, assign yard positions against the dock plan and issue move orders digitally typically operate at a median dwell of 45 to 75 minutes for a live load, with a 90th percentile inside the free-time window. Drop-and-hook operations run lower on paper but move the problem into trailer pool management, where dwell shows up as aged equipment rather than as waiting drivers.
The target that matters commercially is not a number in isolation. It is a 90th percentile that sits inside your contractual free time, because at that point detention stops being a monthly negotiation and carriers stop pricing your unpredictability into the rate.
