A fuel surcharge is a formula, not a gesture. The usual structure is an index, a peg price below which the surcharge is zero, and a divisor in miles per gallon that converts the amount above peg into a per-mile figure. Three details then move the number that prints: which index week is used, whether the surcharge keys to pickup or delivery date, and whether it is paid on loaded miles only or on all miles. On a percentage-pay statement the further question is whether the surcharge sits inside the percentage base or is paid on top. None of those facts are visible in a single dollar figure, which is why a surcharge line with no index, no week, no miles and no formula is not auditable.
The surcharge is a formula sitting in block two
On the settlement, fuel surcharge is an accessorial: it belongs with detention, layover and stop-off, not inside the linehaul row and not inside the deduction block. The how-to-read guide in this set covers that layout. What this page covers is the arithmetic that produces the line, because a surcharge that looks “about right” is usually right in the multiplication and wrong in one of the inputs.
The usual structure has three moving parts. An index is the published diesel price the programme keys to. A peg is the index level below which the surcharge is zero. A divisor, expressed as miles per gallon, converts the amount the index sits above the peg into a per-mile figure. Change any one of the three and the printed line changes even if the truck burned the same fuel on the same trip.
In the United States the index is usually a weekly retail diesel average published by the Energy Information Administration. Canadian programmes commonly key to a Canadian diesel index instead, and some carriers publish their own table. The index is not the price you paid at the pump that day. A statement that cites “diesel” with no publisher, no region and no week is citing a mood, not a source.
Which week, which date, which miles
Diesel indexes are published on a schedule, usually weekly. The programme has to say which week’s figure applies to a given load: the week of pickup, the week of delivery, or a table published in advance for a named period. Carriers that “true up” a month later are running a different programme than carriers that lock the week at dispatch, and the settlement has to show which one you are on.
The date the surcharge keys to is a separate choice from the week. A load picked up on a Thursday and delivered the following Monday can sit on two different index weeks. If the programme keys to pickup, the Thursday week wins; if it keys to delivery, the Monday week wins. That is not a rounding issue. It is a different input.
Miles are the third input, and the one most often left unnamed. Some programmes pay the surcharge on loaded miles only. Some pay it on all dispatched miles, including empty repositioning. Some pay it on the same mileage basis as linehaul (practical, shortest, household-goods) and some on a different one. A surcharge computed on short miles while linehaul is paid on practical miles will never match a back-of-the-envelope check that uses one mileage number for both.
Where the surcharge sits on a percentage-pay statement
On a per-mile or flat-rate statement the surcharge is usually a line of its own: miles times the per-mile surcharge. On a percentage-pay statement there is an extra question the percentage-pay guide in this set covers in full: is the surcharge inside the number the percentage is taken of, or is it paid on top, in full or in some stated share?
Both treatments are common and both are legitimate when the lease says so. What is not legitimate is a statement that does not say which one it is doing. If the surcharge is inside the percentage base, a change in the index moves both the surcharge line and the linehaul percentage. If it is paid on top, a change in the index moves only the surcharge line. You cannot audit the row until you know which of those two machines you are looking at.
In the United States, where an owner-operator leases equipment to a federally authorised for-hire carrier, the truth-in-leasing rules give a documented right to see the rated freight bill the percentage was computed from. Use it. The surcharge treatment is one of the things that bill will show.
Pass-through, table, and the line that never moves
A pass-through programme reprints the formula every period: the index moved, the line moved. A table programme publishes a cents-per-mile (or per-trip) figure for a named period and holds it until the next table. Both are formulas. A table is just a formula that has been evaluated in advance.
The line that never moves is the one to question. Fuel prices move. If the surcharge on your statement is identical across a stretch of weeks in which the published index was not, either the programme is a table that has not rolled, or the line is a placeholder that is not actually computing. Ask which, in writing, and keep the answer with the lease.
A zero surcharge can be correct. When the index sits at or below the peg, the formula produces nothing. A zero line with the index, week and peg named next to it is a computed zero. A missing line, with no mention of the surcharge at all, is a different fact: it was never built, which is the missing-accessorial problem the accessorial guide in this set covers.
What a readable surcharge line shows
At minimum: the index name and week, the peg, the divisor, the miles it was applied to, and the resulting per-mile or per-trip figure. A load number that ties it to the same trip as the linehaul row. If the programme uses a published table, a reference to the table and the period it covers.
If any of those are missing you cannot reconstruct the line from public information plus your own trip sheet, which is the whole point of a formula. Asking the settlement clerk to print the inputs is a documentation request, not a dispute. The dispute, if the inputs are present and the multiplication is still wrong, is a shortage, and that procedure lives in the pay-shortage guide in this set.
Do not confuse this line with the IFTA or fuel-tax true-up. Fuel surcharge is a customer-facing (or lease-facing) recovery of diesel cost. IFTA is a jurisdictional fuel-tax reconciliation. They can both appear on the same statement and they are not substitutes. The IFTA guide in this set covers the tax line.
The pump price is not the audit
What you paid at the truck stop is a cost. The surcharge is a contractual recovery keyed to a published index. Those two numbers are not supposed to match, and a week in which you paid more than the index is not, on its own, evidence that the surcharge is short. The evidence that the surcharge is short is that the formula in the lease, applied to the named index week and the named miles, does not produce the printed line.
Fuel-card purchases recovered as a deduction are a third thing again. That recovery is an advance against unsettled work, covered by the advances-and-fuel-cards guide in this set. A driver who tries to net the surcharge against the fuel-card deduction is mixing an earning line with a recovery line. They can both be correct and the net can still feel wrong, which is a reading-order problem, not a surcharge problem.
FAQ
What is a fuel surcharge on a trucking settlement?
It is a contractual line that recovers diesel-cost movement using a published index, a peg below which the surcharge is zero, and a divisor that turns the amount above peg into a per-mile (or per-trip) figure. It is not the price you paid at the pump, and it is not an IFTA true-up.
Why is my fuel surcharge different from what I paid for diesel?
Because the surcharge keys to a published index for a named week, not to your pump price. The two are not supposed to match. Audit the line against the formula in your lease — index, peg, divisor, miles — not against your fuel receipts.
Is fuel surcharge paid on empty miles?
Only if the programme says so. Some pay on loaded miles only, some on all dispatched miles, some on the same mileage basis as linehaul and some on a different one. The statement should name the miles. If it does not, ask, because that single fact moves the line.
Does a percentage-pay lease include the fuel surcharge in the percentage?
Sometimes the surcharge sits inside the percentage base; sometimes it is paid on top, in full or in a stated share. Both are common. The statement and the lease have to say which. In the United States, a leased-on owner-operator also has a documented right to see the rated freight bill the percentage was computed from.
A zero fuel surcharge — is that an error?
Not if the index is at or below the peg and the statement names those inputs. A computed zero is a real result. A missing surcharge line, with no mention of the programme at all, is the different problem of an accessorial that was never built.
Is the fuel surcharge the same as the IFTA line?
No. Fuel surcharge recovers diesel-cost movement under the lease or the customer tariff. IFTA is a jurisdictional fuel-tax reconciliation, often recovered or credited as a separate true-up. They can both appear on one statement and they audit against different documents.
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