Accessorial charges are fees beyond the base freight rate, and they can add 15-30% to total shipping cost (often surprising shippers who forget to factor them in). The quoted linehaul rate covers moving the freight from origin to destination. Accessorials cover all else that happens along the way, the waiting, the storage, the extra equipment, the second trips.
And during congestion, they are where freight budgets quietly come apart. Essentially, these added charges are anything and everything from origin to destination that falls outside what the shipper asked their carrier to quote.
Accessorials are the least transparent part of a freight quote and the easiest to overlook when comparing options. Two quotes with identical linehaul rates can land very differently once accessorial charges are counted, and the difference often comes down to how well the move was orchestrated and how clearly its requirements were communicated, not how it was priced. A requirement the carrier can see coming can often be built into the linehaul at a lower rate than the same requirement billed as an accessorial after the fact.
Detention is one example: a shipper who knows a lane will need more than the standard free time to load or unload, and says so when asking for the quote, lets the carrier price that time into the move instead of charging it reactively. The same holds across most accessorials. What the carrier can plan for, it prices efficiently; what surprises the move, it charges to recover.
This guide explains the major accessorial charges, what triggers each one, and how a shipper can limit exposure, with the most attention on the intermodal, drayage, and port charges where the confusion runs deepest.
Key Takeaways:
An accessorial charge is any fee beyond the base transportation rate. The linehaul moves the freight, then the accessorials cover the additional services, delays, and equipment that the move requires - all fees not included in the base rate.
Some accessorials are predictable and built into a move from the start, a residential delivery, a liftgate, an additional stop. Others are triggered by what happens during execution, a driver held too long at a dock, a container that sits past its free time, an appointment that gets missed. The first kind can be planned and quoted. The second kind is where exposure builds, because it depends on conditions at the facilities, the ports, and the ramps - conditions that tighten exactly when the freight market is busiest.
For a shipper, the real cost of a move is the linehaul plus the accessorials, and the accessorials are the part you have the most ability to influence through planning and execution. Understanding them is the first step to controlling them.
Detention, demurrage and per diem are the three charges that cause more confusion than any others in freight, because they sound similar: They all relate to time, and they apply at different points in the move.
Detention is the charge for holding a truck or driver beyond the free time allotted for loading or unloading. Two hours at origin and two at destination are typical, but not every carrier is typical, so it pays to read the fine print. Free time is set by the carrier and varies, and the number that governs your move is the one written into your contract or the carrier's tariff, not the industry rule of thumb. Past the free window, detention accrues, typically by the hour, to compensate the carrier for time the driver and equipment cannot spend earning on another load.
Detention applies in both truckload and drayage. In drayage, it shows up when a dray driver is held at a shipper, consignee, or terminal beyond the free window. Because a drayage driver's day is built around turn times, detention at one stop can cascade into missed appointments at the next, which is part of why drayage detention is more disruptive than the dollar figure alone suggests.
Demurrage is the charge for cargo that sits at a port or rail terminal beyond its allotted free time. When an import container lands at a marine terminal, the shipper has a set number of free days to pick it up. Past that window, demurrage accrues for each day the container occupies terminal space. The terminal is, in effect, charging rent for the ground the container is sitting on.
One detail catches shippers off guard: Free time is frequently counted in calendar days, not business days, so the clock can keep running on weekends and holidays when the terminal is closed and the container cannot be retrieved. A box that lands right before a long weekend can burn free days no one could have used. That is why demurrage is managed by tight operational timing as much as by the free-day count, getting the appointment, the chassis, and the dray lined up so the container moves the moment it becomes available.
The cleanest way to keep demurrage separate from detention: Demurrage is the container sitting inside the terminal too long, waiting to be picked up. Detention, in the ocean equipment context, is the container kept outside the terminal too long, at your facility, beyond the free time the carrier allows before they want their equipment back. Inside the gate is demurrage. Outside the gate is detention. Same idea, opposite side of the fence.
How ocean demurrage and detention can be billed is regulated, which works in the shipper's favor. Under the Ocean Shipping Reform Act of 2022, the Federal Maritime Commission set requirements for these invoices, including the information a bill has to show, a 30 day window to issue it, and a process for disputing charges. A shipper who receives an ocean demurrage or detention bill has more standing to question it than many assume, and the FMC's billing rule is the reference for what a valid invoice must contain.
Per diem is the daily charge for using a railroad's or carrier's equipment beyond the allotted free days. In the intermodal context, when you use a rail-provided container or chassis, you get a set number of free days. Hold the equipment past that, and per diem accrues per day until it is returned. Per diem is the rail-and-equipment cousin of detention: where detention charges for holding a truck and driver, per diem charges for holding the box and the wheels.
These three matter together because an import intermodal move can touch all three. The container can sit at the port too long (demurrage), the dray can be held at your dock too long (detention), and the equipment can be returned late (per diem). Each is a separate clock, and a shipper watching only one of them can still be caught by the other two.
Import and intermodal freight carries a set of charges tied to the equipment (like drayage) and the congestion at ports and ramps. These are where the education gap is widest, because they have no equivalent in a simple over-the-road truckload move.
How these reach the shipper depends on the provider. Many intermodal providers, though not all, roll the predictable ones, chassis usage, a required pre-pull, the expected storage, into the quoted price, so they never surface as separate line items. That is the typical approach, but importantly, not a universal one. Because IMCs do not all quote the same way, the questions worth asking at quote time are simple: what is included, and what is billed separately. Read the fine print before you compare two numbers that may not cover the same things.
Even charges folded into the quote can land on the accessorial side of the invoice when the move does not go as assumed. A quote prices the move the provider expects. If the shipment hits a delay that was not built into that assumption, the container dwells longer, the chassis is held longer, storage runs past what was planned, and the overage comes back as an accessorial.
Chassis charges. A chassis is the wheeled frame that carries the container on the road. Chassis usage is billed daily, and the cost can add up when a container dwells. A related and often surprising charge is the chassis split, which occurs when the chassis and the container are not in the same place and the dray driver has to make an extra trip to bring them together. That second trip is billable, and in congested markets chassis splits are common.
Storage. When a container or its cargo sits at a yard, ramp, or warehouse beyond the allotted time, storage charges accrue. Storage overlaps conceptually with demurrage but is typically assessed off-terminal, at a rail ramp or a third-party yard, rather than at the marine terminal.
Pre-pull. A pre-pull is when a dray carrier pulls a container from the terminal before its scheduled delivery appointment, usually to avoid mounting demurrage or to work around appointment timing, and stages it at their own yard. The pre-pull move and the short-term storage that follows are billable. Used well, a pre-pull is a congestion-management tool that can cost less than the demurrage it avoids. The point is to treat it as a deliberate trade, not a surprise.
Congestion and appointment-related fees. In the busiest port and ramp markets, additional fees can attach to terminal congestion, appointment systems, and equipment imbalances. These vary by market and by terminal, which is why local knowledge of where freight concentrates is part of managing the cost.
Over-the-road truckload carries its own set of accessorials, most of them tied to time, labor, and changes to the planned move.
Detention applies here as it does in drayage, for time held beyond the free window at a dock. Layover applies when a driver is held overnight, unable to load or unload as scheduled. Lumper fees cover third-party labor hired to load or unload at a facility - common in grocery and food distribution. Redelivery is charged when a delivery cannot be completed and must be reattempted. Truck Ordered Not Used (TONU) applies when a truck is dispatched for a load that then cancels, compensating the carrier for the committed capacity. Stop-off charges apply to additional pickups or drops beyond the first.
None of these charges are out of bounds, as they are additional costs that are incurred by a carrier because the shipment did not move as planned. But all of these charges are avoidable or reducible with planning, accurate appointment scheduling, and realistic dock expectations.
| Charge | What it covers | What triggers it | How to limit it |
|---|---|---|---|
| Detention | Truck/driver held beyond free time at a facility | Slow loading or unloading past the free window (often ~2 hrs) | Efficient dock scheduling, accurate appointments, realistic dwell expectations |
| Demurrage | Container dwelling inside a port or rail terminal past free time | Container not picked up within the free-day window | Pick up promptly, track free time, consider a pre-pull when appointments are tight |
| Detention (equipment) | Container/equipment held outside the terminal past free time | Holding the carrier's equipment at your facility beyond the allowed days | Unload and return equipment promptly, monitor free days per container |
| Per diem | Daily use of rail/carrier equipment beyond free days | Holding rail-provided containers or chassis past the free window | Return equipment on time, build realistic unload-and-return windows |
| Chassis usage | Daily rental of the chassis carrying the container | Chassis in use over multiple days; container dwell | Minimize dwell, plan chassis sourcing in advance |
| Chassis split | Extra dray trip to pair a chassis with a container | Chassis and container in different locations | Coordinate equipment sourcing; work with a drayage provider that manages chassis pools |
| Storage | Container/cargo held at a yard or ramp beyond allotted time | Off-terminal dwell at a ramp or third-party yard | Schedule timely delivery, position inventory to absorb arrivals |
| Pre-pull | Pulling a container before the delivery appointment and staging it | Appointment timing or demurrage avoidance | Use deliberately as a trade against demurrage, not as a default |
| Layover | Driver held overnight | Inability to load or unload as scheduled | Accurate scheduling, ready freight at appointment time |
| Lumper | Third-party loading/unloading labor | Facility requires hired labor (common in food/grocery) | Anticipate and budget; confirm facility requirements upfront |
| Redelivery | Reattempted delivery after a failed first attempt | Missed or refused delivery | Confirm receiving readiness and appointment accuracy |
| TONU | Truck dispatched for a canceled load | Load cancellation after dispatch | Firm up tenders before dispatch; communicate changes early |
Accessorials do not accrue evenly through the year. They cluster during congestion, and congestion clusters during peak season.
When ports, ramps, and distribution centers back up, every clock that drives an accessorial speeds up. Containers wait longer to be picked up and demurrage builds. Equipment cycles more slowly, lifting per diem and chassis charges. Docks fall behind and detention climbs, while slipping appointments multiply pre-pulls and redeliveries. The same conditions that make capacity scarce during peak also make accessorials expensive, and the two compound. A shipper focused only on the linehaul during peak can be blindsided by an accessorial bill the rate comparison never hinted at.
Peak season is where this bites hardest. The accessorial exposure is part of the real cost of moving freight through a tight market, and building it into the plan rather than discovering it on the invoice is what separates a peak budget that holds from one that does not. For the full planning picture, see our shipper's guide to peak season freight planning.
For intermodal and import freight, accessorial exposure largely comes down to orchestration across the three legs of the move: the origin drayage, the linehaul, and the destination drayage. Each leg has its own clocks and its own equipment, and a delay or misstep on one leg can trigger charges on another. A container that misses its dray appointment can sit at the ramp and accrue storage. Equipment returned late after delivery accrues per diem. A chassis sourced from the wrong location triggers a split.
Coordination of the move matters as much as the rate of it. The party orchestrating all three legs can see the clocks, sequence the equipment, and catch the timing problems before they become charges. Most accessorial cost on intermodal freight is controlled or lost in that orchestration rather than the negotiated linehaul. A shipper evaluating providers is right to ask not only what the rate is, but how the accessorials will be managed across the full move. For more on the drayage leg, see our guide to understanding drayage and intermodal service.
If you would like to understand the accessorial exposure on your specific lanes, visit the InTek Logistics blog. If you would like a lane-by-lane evaluation, we are here to help.
Related Reading:
An accessorial charge is any fee beyond the base linehaul rate. It covers additional services, delays, and equipment that a move requires but the linehaul does not include, such as detention, demurrage, per diem, chassis fees, storage, and special handling. The real cost of a move is the linehaul plus the accessorials.
Demurrage is charged when a container sits inside a port or rail terminal beyond its free time, waiting to be picked up. Detention is charged when a truck or driver is held beyond the free time at a facility, or, in the ocean equipment context, when the carrier's container is held outside the terminal at your facility beyond the allowed days. Inside the terminal is demurrage. Outside the terminal, or at the dock, is detention.
Per diem is the daily charge for holding a railroad's or carrier's equipment, such as a container or chassis, beyond the allotted free days. It is the equipment equivalent of detention: where detention charges for holding a truck and driver, per diem charges for holding the box and the chassis past the free window.
A chassis split occurs when the chassis and the container are not in the same location and the drayage driver has to make an extra trip to bring them together. That additional trip is billable. Chassis splits are more common in congested markets where equipment is imbalanced.
A pre-pull is when a drayage carrier pulls a container from the terminal before its scheduled delivery appointment and stages it at their own yard, usually to avoid mounting demurrage or to work around appointment timing. The pre-pull move and the short-term storage are billable, but used well it can cost less than the demurrage it avoids.
Accessorials are driven by time and congestion. During peak, ports, ramps, and distribution centers back up, which slows every clock that drives a charge. Containers wait longer (demurrage), equipment cycles slower (per diem and chassis), and docks back up (detention). The same congestion that tightens capacity also drives accessorial costs higher.
Many accessorials can be reduced, and some avoided entirely. Predictable requirements, like a known need for extra load time or a specific chassis, can often be disclosed upfront and priced into the linehaul, which usually costs less than the same charge billed after the fact. Execution-driven charges like detention, demurrage, and per diem come down through tighter scheduling and faster equipment turns. The hardest to control are market-driven congestion fees, though even those can be budgeted for. The rule of thumb: disclose what you can predict, and tighten execution on what you cannot.
Track free time on every container, tighten dock and appointment scheduling, treat pre-pulls as a deliberate trade against demurrage, build accessorial exposure into peak budgets, and understand how a provider orchestrates the origin dray, linehaul, and destination dray, since that coordination is where most intermodal accessorial cost is controlled or lost.
This guide is part of InTek Logistics' shipper education library, providing data-driven, mode-neutral analysis of intermodal, truckload, and drayage to help shippers make better freight decisions.
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