How truck freight rates are calculated: linehaul, fuel surcharges, accessorials and market forces

Truck freight prices can look opaque, but most bills are built from the same few pieces: a base charge for moving the freight, a fuel surcharge and charges for extra services. What changes is how each piece is calculated and what the market looks like on that route. This guide breaks down the parts and the forces behind them. It does not quote rates, which vary by carrier, lane and date.

What goes into a freight bill

Federal rules at 49 CFR 373.103 require for-hire, non-exempt motor carriers of property to issue a freight or expense bill for each shipment that shows, among other things, the exact rates assessed and the total charges due, including the nature and amount of any charges for special service. In practice, most bills combine three components:

• Linehaul: the base charge for moving the freight from origin to destination.
• Fuel surcharge: an adjustment that moves with diesel prices.
• Accessorial charges: fees for services beyond a standard dock-to-dock move.

Linehaul: the base rate

The Federal Highway Administration's freight glossary defines line haul as "the movement of freight over the road/rail from origin terminal to destination terminal, usually over long distances." How it is priced depends on the service:

• Full truckload linehaul is usually quoted per mile or as a flat price for the load. Because the shipper pays for the whole trailer, distance, equipment type and the lane matter more than what the freight is.
• Less-than-truckload (LTL) linehaul is usually based on the freight's NMFC class, its weight and its origin and destination. It is commonly calculated from the carrier's rate tables, with any negotiated discount applied and a minimum charge per shipment.

Fuel surcharges and the EIA diesel price

"Many shipping and delivery companies and freight carriers include a fuel-cost surcharge in their rates and invoices," the U.S. Energy Information Administration (EIA) notes on its fuel surcharge page. EIA publishes the retail diesel prices that many shippers and truckers use in those calculations, but it does not calculate, assess or regulate surcharges, and it does not endorse any method. Each company sets its own formula.

The figure most often referenced is EIA's weekly U.S. average retail price for on-highway diesel. According to EIA's methodology, it is based on the cash, self-serve pump price, including taxes, at a sample of truck stops and service stations as of 8:00 a.m. local time each Monday. EIA publishes the estimates around 10:00 a.m. Eastern time on Tuesday, or on Wednesday after a government holiday.

In EIA's Gasoline and Diesel Fuel Update released October 6, 2026, the U.S. average on-highway diesel price for October 5, 2026 was $6.199 per gallon, about $2.49 higher than a year earlier. The figure changes every week, so it is worth checking the current release.

A surcharge schedule typically sets a base diesel price and adds a charge as the EIA average rises above it. Truckload surcharges are commonly stated in cents per mile and LTL surcharges as a percentage of the linehaul charge, though formulas vary. As a hypothetical example, a contract might add a fixed number of cents per mile for every 5-cent rise in the EIA average above the base price. Shippers can ask each carrier for its schedule and for the EIA series it uses, since EIA also publishes regional averages.

Accessorial charges

Accessorial charges cover work beyond picking up at one dock and delivering to another. Each carrier sets its own in a rules tariff or contract, and names and amounts vary. Common examples include:

FHWA's glossary describes detention fees as charges applied when equipment is "retained beyond a specified loading or unloading time," and lumpers as people who assist with unloading, "quite commonly used in the food industry." Federal law also addresses who pays for that help. Under 49 U.S.C. 14103, when a shipper or receiver requires that a truck be assisted in loading or unloading, it must provide the help or compensate the vehicle's owner or operator for the cost, and coercing a carrier to pay for that help is unlawful.

Lanes, balance and seasonality

A lane is the route between an origin and a destination, and two lanes of the same length can price very differently. A big reason is what happens after delivery. FHWA's glossary defines a backhaul as a vehicle returning from its destination toward its origin, which can be loaded or partly loaded, and deadhead as an empty return. If an area ships out little freight, a carrier may have to drive empty to its next load, and prices into that area can reflect that cost. Lanes into busy shipping regions, where a return load is easier to find, can price lower.

Rates also move with the calendar. Harvest seasons, holiday retail peaks and severe weather can tighten truck capacity in particular regions. The U.S. Department of Agriculture's Agricultural Refrigerated Truck Quarterly, a public report on produce trucking, shows rates per mile shifting from quarter to quarter and differing between short and long hauls.

Spot vs. contract rates

Spot rates are prices for a single shipment, quoted to move it now. They reflect current conditions on the lane: when trucks are plentiful, spot prices tend to fall, and when capacity is tight, they tend to rise.

Contract rates are negotiated in advance, typically for specific lanes over a set period, often with expected volumes and an agreed fuel surcharge schedule. They make budgeting more predictable, but a carrier may decline loads beyond the agreed volume, and the contract price can end up above or below the market as conditions change.

Many shippers use contract rates for steady lanes and spot quotes for one-off loads.

Checking a freight bill

• Compare each line to the quote, including the fuel surcharge week and the EIA price used.
• Look for accessorial charges that were not requested, and ask for supporting records, such as arrival and departure times for detention.
• For LTL, confirm that the class, weight and dimensions match what was tendered.
• Ask for the rules behind any charge. Under 49 U.S.C. 13710, a motor carrier of property must provide, on request, a copy of the rate, classification, rules and practices its charges are based on, and a shipper that wants to contest a bill must do so within 180 days of receiving it.