What a fuel compliance rate is, and how to calculate one.

What the number counts

A fuel compliance rate is the proportion of your fuel purchasing that happened inside your discount network. Everything else — a station that is not on your provider's site list, a fill on a personal card that gets expensed later — is outside it.

That is the whole definition, and the simplicity is deceptive, because two carriers can both say "we are at a high compliance rate" and be measuring different things. The disagreements are about the denominator, the period, and what counts as a purchase at all. Settle those three and the number becomes comparable to itself over time, which is the only comparison that matters.

Gallons or transactions, and why the two disagree

You can count transactions — what share of fills were in-network — or gallons, what share of fuel volume was. Both are legitimate and they answer different questions.

Transactions tell you how consistently the program is followed. Gallons tell you how much of your actual fuel spend it governs. They diverge whenever off-network fills are unusual in size, and off-network fills are exactly where unusual sizes live: a driver who tops off a quarter tank at a convenient station creates a transaction with few gallons behind it, while a driver who runs dry in a coverage gap and takes a full fill creates one transaction carrying a large volume.

So a fleet can look disciplined by transaction count and much worse by gallons, or the reverse, from exactly the same data. Neither number is wrong. Reporting one without saying which is what makes a compliance rate unfalsifiable.

If you only want one, use gallons, because gallons are what the discount applies to. Keep the transaction count beside it, because that is the one that tells you whether the behaviour is changing.

What period to measure over

A month is the shortest period worth reporting, because it matches the billing cycle you will reconcile against and it is long enough to absorb a single awkward week.

Measure a rolling twelve months alongside it. Fuel buying is seasonal, lanes change, and a fleet that compares January to December learns nothing except that January and December are different. The rolling figure is what tells you whether the program is working; the monthly figure is what tells you whether something just broke.

How to derive it from a fuel-card export

Everything you need is in the transaction export your card provider already produces. Ask for it as a CSV.

For each transaction you want the date, the truck, the driver, the station identifier, the gallons and the amount settled. Join the station identifier against your provider's current site list — current, because networks add and drop sites, and a stale list will quietly reclassify fills that were in-network when they happened.

Then sum gallons by side of that join, and divide in-network gallons by total gallons. Do the same with a count of rows for the transaction version. That is the whole calculation; the work is in the join, not the arithmetic.

Two things will go wrong the first time. Some rows will not match any site, because the identifier format can differ between the export and the site list — resolve those by hand rather than dropping them, because unmatched rows are exactly the population you are trying to measure. And some rows will not be fuel at all: scale tickets, oil, cash advances. Decide explicitly whether those are in scope, write the decision down, and apply it the same way every month.

What the number does not tell you

A compliance rate is a measure of where fuel was bought, not of whether it was bought well. A fleet can be fully in-network and still be paying more than it needs to, by filling at the in-network station with the weakest net price on the lane rather than the strongest.

It also says nothing about whether the stop was reachable. A gap on a lane with no in-network option inside a sane detour produces off-network fills that no amount of coaching will fix, and counting them against the driver teaches the fleet to argue with the number rather than act on it.

Pair it with net price per gallon and with a per-lane view, and it becomes a management number. On its own it is a reporting number.

Questions

What is a good fuel compliance rate?

There is no industry figure worth quoting, and anyone who gives you one without asking about your lanes and your network is guessing. The useful target is relative: measure where you are, then set a number your own network coverage can actually support on your own lanes.

Should personal-card fills that get expensed count against it?

Decide once and apply it consistently. They are fuel your contract did not govern, so counting them is defensible; excluding them is also defensible if they are rare and reimbursed outside the fuel process. What is not defensible is changing the answer between periods, which makes the trend meaningless.

Our provider reports a compliance rate already. Why calculate our own?

Because you will not know what it counts. A provider's figure uses their denominator, their site list and their period, and those are reasonable choices that may not be yours. Deriving it yourself from the same export is cheap and makes the number yours to defend.