Fuel is the biggest line in your cost book after the truck itself. Three mechanisms decide whether it eats your margin or behaves: the card, the surcharge, and the advance.
The card: pump price is negotiable
Fleet fuel cards get carrier-negotiated pricing — typically cost-plus at major truck-stop chains rather than the cash price on the sign. Across 2,500 miles a week, even a modest per-gallon discount compounds into thousands a year. If you're leased on, the discount your carrier negotiated is part of your compensation; know what it is.
The surcharge: it's your money
Brokers pay a fuel surcharge on most loads, meant to buffer diesel price swings. The question to ask any carrier: is the surcharge passed through to the driver as its own line, or folded into the rate where it can quietly shrink? On an honest settlement, you'll see it separately. If you can't see it, you can't verify it.
The advance: a tool, not a trap
A fuel advance against a load in progress smooths cash flow on long runs. Used well, it's plumbing. The things to check are the fee (flat or percentage), where it appears on the settlement, and whether it's itemized against the specific load. An advance that shows up as an unexplained deduction two weeks later is a bookkeeping problem you don't need.