Trucking Fuel Discounts: Three Ways Enterprise Fleets Overpay at the Pump (With Real Numbers)

Fuel is the second largest operating expense in trucking, trailing only driver wages. For a mid-size fleet running 50 trucks, annual diesel spend commonly lands between $1.5 million and $2.5 million depending on routes, equipment age, and fueling habits. That is a number most fleet directors know.

What most do not know is how much of that number they are giving away unnecessarily, and through which specific channels the money leaves.

The trucking industry has focused most of its attention on fuel price volatility, the swings in diesel that nobody can fully control. What gets less attention is the controllable portion: the gap between what a well-managed fleet pays for fuel and what a poorly managed one pays for the same miles. That gap, built from three distinct overpayment problems, is consistently larger than fleet managers expect when they finally run the numbers.

This article breaks down all three, puts real dollar figures on each, and explains what the practical correction looks like for a fleet actually trying to close the gap.

Why "We Have a Fuel Card" Is Not the Same as "We Have a Fuel Discount Strategy"

Before getting into the three problems, it is worth addressing the assumption that derails most fleet fuel conversations. Many fleet managers believe that because their operation uses a fuel card, the fuel discount problem is solved. It is not, and the research is clear on this.

A fuel card provides access to a discount structure. Whether that structure actually delivers net savings, and how large those savings are, depends entirely on which card you have, which network your drivers actually fuel at, how the card's fee structure interacts with its rebate tiers, and whether the program matches your routes. A fleet with the wrong card for its lanes may technically be receiving a 5-cent-per-gallon rebate while simultaneously fueling at stations that are 20 cents per gallon above the lowest-priced option on the same route. The "discount" becomes a cost.

This matters because the three overpayment problems outlined below exist independent of whether a fleet has a fuel card. They exist in operations with cards, without cards, and in operations running cards that are structurally misaligned with how the fleet actually operates.

Overpayment Problem 1: The Retail Pricing Gap

The most straightforward way a fleet overpays on fuel is by consistently purchasing at or near retail pump price when discounted pricing is available, either because no fuel card program is in place, because the program in place does not match the fleet's fueling geography, or because the card's discount structure sounds better than it performs in practice.

The numbers on this gap are significant. Distribution and marketing costs alone account for approximately 19 percent of the retail diesel price that fleets pay at the pump. Fleets accessing wholesale or cost-plus pricing structures bypass most of that premium. For a fleet consuming 100,000 gallons annually at a national average of roughly $3.70 per gallon, that 19 percent distribution markup represents around $70,300 in retail-inflated costs that a better-structured program could substantially reduce.

For fleets that do have cards, the gap between a poorly matched program and a well-matched one also runs wide. The difference between a card delivering 5 cents per gallon at stations your drivers do not primarily use and a card delivering 40 to 44 cents per gallon at the truck stops they actually stop at is, at 100,000 gallons annually, the difference between $5,000 in annual savings and $40,000 to $44,000. That gap does not require any change in driving behavior, route structure, or equipment. It requires picking the right program.

The pricing structure of the card matters as much as the advertised discount. There are two primary models in the market. Retail-minus cards subtract a set rebate from whatever the pump price is at the station, meaning your savings are only as good as the station's posted price. Cost-plus cards price fuel at the OPIS wholesale rate plus a fixed program fee, which means drivers fueling at different locations in the same market pay roughly the same price regardless of which station's posted price happens to be higher that day. For fleets with drivers covering variable routes and fueling at multiple locations, cost-plus pricing can eliminate the variance that retail-minus structures leave uncontrolled.

The volume tier problem compounds this further. Most fuel card programs structure their best rebate rates at the highest monthly volume tiers. An enterprise fleet with 50 trucks that splits its fuel spend across two or three card programs to "give drivers flexibility" may never hit the volume threshold for the top rebate tier on any of them, while the same fleet consolidating to a single program would qualify for the best rate available. This is one of the specific costs described in what fragmented vendor relationships really cost a fleet: distributed spend means forfeited leverage.

Overpayment Problem 2: Fuel Fraud and Internal Theft

The second overpayment problem is less comfortable to discuss but significantly larger in dollar terms for most fleets. Fuel fraud, defined broadly to include card skimming, unauthorized purchases, internal misuse, inflated mileage reporting, and drivers fueling personal vehicles on company cards, is a systematic leak that most fleets are underestimating.

The data here is striking. WEX's 2024 research found that five to ten percent of a fleet's annual fuel consumption is lost to theft or misallocation, with fraud rates reaching as high as 12 percent in 2024. Motive's Physical Economy Outlook, drawing on data from surveyed fleet operations leaders, found that 19 to 22 percent of fleet spend overall is lost to fraud or theft. The National Association of Fleet Administrators estimates that fuel theft specifically can account for up to 6 percent of a fleet's total fuel cost.

These are not small numbers. A fleet spending $2 million annually on fuel that is losing 6 percent to theft and misuse is giving away $120,000 per year. At 10 percent, that is $200,000. Most of that money does not announce itself. It shows up as slightly elevated fuel spend that looks like it could be explained by route changes, price increases, or seasonal variation. Without transaction-level reporting tied to vehicle GPS data, it can accumulate for months before anyone identifies the pattern.

Card skimming alone has become a more urgent problem. Incidents of commercial fuel card skimming grew approximately 70 percent year-over-year from 2022 to 2023. The fraud is sophisticated: skimming devices capture card data at the pump, and stolen card information is used to make unauthorized purchases that appear as normal fuel transactions until the billing reconciliation catches an anomaly, which in many operations happens weeks after the fact.

The internal theft component is the one most fleet managers are reluctant to address directly. A driver who fills a personal vehicle at $50 per transaction, twice a week, costs the fleet $5,200 per year from a single card. Scaled across a fleet of 50 drivers where even 10 percent of drivers do this, the annual loss is $26,000. Without per-transaction purchase controls, time and location restrictions, and odometer validation requirements, the data needed to identify this pattern simply does not exist.

Modern fuel card programs with robust controls can catch the majority of this exposure. Cards that require PIN entry, odometer input at each transaction, and flag purchases that exceed vehicle tank capacity stop the most common forms of misuse at the point of transaction rather than in a monthly reconciliation. Fuel card integration with GPS telematics, where the card's transaction data is cross-referenced against the vehicle's actual location at the time of the purchase, can intercept fraudulent transactions in real time. Programs with these features do exist, and they are available at the network scale that enterprise fleets require.

Overpayment Problem 3: Passive Operational Waste

The third overpayment category is the one nobody is committing on purpose. It does not show up in a fraud report. No driver is deliberately wasting fuel in a way that is easily visible. But it accumulates continuously across every truck in the fleet, and the data on its scale is well-established.

Idling is the most quantified form of this problem. A Class 8 truck burns approximately 0.8 to 1 gallon of diesel per hour while idling, according to research from the North American Council for Freight Efficiency (NACFE). A single long-haul truck that idles two hours per day burns over 700 gallons per year in fuel that produces zero miles. At $3.70 per gallon, that is roughly $2,590 per truck, per year, in fuel that goes nowhere. NACFE estimates that overnight idling alone wastes between $4,000 and $6,000 worth of fuel annually per long-haul truck. A fleet of 50 trucks with unmanaged overnight idling can be losing $200,000 to $300,000 per year from this single behavior.

One report from the U.S. Office of Energy Efficiency found that 39 percent of the studied fleet vehicles idled three to four hours per day, and 14 percent idled for more than four hours daily. Only 34 percent idled for less than an hour. That distribution means the average truck in an unmonitored fleet is almost certainly idling well beyond what any fleet director would consciously approve as acceptable policy.

Driver behavior beyond idling compounds the problem further. Research from Automotive Fleet has documented that up to 30 percent of a vehicle's fuel efficiency can be affected by driver behavior, including speed management, hard acceleration, aggressive braking, and gear selection. The NACFE 2024 Fleet Fuel Study, tracking 14 participating fleets operating 75,000 trucks, found that disciplined drivers consistently achieved 7.8 miles per gallon or better in identical equipment, compared to a national average hovering around 6.9 MPG. That 13 percent fuel efficiency gap between average and disciplined driving, multiplied across a fleet of 50 trucks each covering 100,000 miles annually, represents substantial recoverable savings at any diesel price.

The challenge with passive waste is that it requires visibility to address. A fleet that does not measure idle time per vehicle, per driver, per route cannot set targets, coach drivers, or track improvement. The data does not exist until someone puts a system in place to collect it. This is precisely where telematics programs produce their documented fuel savings: the Verizon Connect 2025 Fleet Technology Trends Report, which surveyed 543 fleet managers, found that fleets using integrated GPS and telematics reported average fuel savings of 16 percent. You cannot reduce what you cannot see.

What the Combined Number Looks Like

It is worth putting the three problems together in one place, with conservative figures, for a 50-truck fleet spending $2 million annually on fuel.

Retail pricing gap: A fleet on a mismatched or absent fuel card program versus one on a well-matched network discount program represents a per-gallon difference of anywhere from 20 to 35 cents at OTR truck stops, based on published program data from major card providers. At 500,000 gallons annually (10,000 gallons per truck), that spread is worth between $100,000 and $175,000 per year.

Fraud and theft: At the NAFA estimate of 6 percent of total fuel cost, the annual loss is $120,000. At 10 percent (within the WEX-documented range), it is $200,000.

Passive operational waste: A conservative 10 percent reduction from improved idling management and driver coaching on a $2 million fuel budget recovers $200,000. Fleets tracking this specifically report 12 to 18 percent fuel savings within 90 days of implementing KPI monitoring, according to fleet efficiency data published by FleetRabbit.

Combined at conservative levels, these three problems represent $420,000 to $575,000 in recoverable annual fuel spend for a 50-truck fleet. That is not a rounding error. At current industry operating margins, which ATRI data shows running below 2 percent in most trucking sectors, $420,000 in recovered fuel cost is the difference between a profitable year and a difficult one.

How Trucking Fuel Discounts Actually Work at the Enterprise Level

For fleet directors building the case internally for a more structured fuel program, it helps to understand the mechanics of how enterprise-level discount access differs from what individual truck programs deliver.

Enterprise fuel card programs negotiate volume-based contracts directly with truck stop networks including Love's, TA Petro, Pilot Flying J, and others. The per-gallon discount available to a fleet channeling its full diesel spend through a single program is categorically different from what a small operator or individual driver can access. Network operators agree to deeper discounts in exchange for guaranteed volume commitments, and those discounts are passed through to the fleet as either retail-minus rebates or cost-plus pricing structures.

The practical implication is that an enterprise fleet running 50 or more trucks that has not negotiated a volume-based fuel program is leaving money on the table that its scale entitles it to claim. The discounts available to large-volume customers exist precisely because the card network needs the volume commitment in order to maintain its contracts with the station networks. Fleets that spread their fuel spend across multiple programs, or that have not actively negotiated their program terms at renewal, rarely access the best rates available.

Understanding your fleet's cost per mile is the essential baseline before any fuel program negotiation. You cannot evaluate a fuel card program's value without knowing your current fuel cost per mile and how a new program's projected savings would move that number. A program that looks impressive in its advertised discount rate may net out poorly after fees if your fleet's fueling patterns do not align with the program's network.

The Structural Fix: What It Actually Takes

Fixing all three overpayment problems at once requires addressing them as a package rather than three separate initiatives, because the tools that solve one tend to support the others.

A fuel card program with volume-based network discounts solves the retail pricing gap. The same card's transaction controls, PIN requirements, and odometer validation directly cut into fraud and misuse exposure. Integrating that card's data with telematics gives you the cross-referenced transaction and location data needed to catch anomalies in real time. The same telematics system that flags unauthorized fuel purchases also captures idle time per driver, speed behavior, and the data needed to build a driver coaching program that reduces passive waste.

This is why how integrated fleet service models reduce fuel costs matters here. Fuel savings in isolation from the broader service structure typically capture only one of the three layers. The largest recoveries come when the fuel program, the telematics data, and the fleet management structure are coordinated rather than running as separate vendor relationships.

For fleet directors ready to act, the first step is not selecting a new card. It is running the audit. Pull three months of fuel transaction data, calculate your current effective cost per gallon by location, identify the percentage of transactions that occur off your drivers' primary routes, and cross-reference high-spend vehicles against their reported mileage. That exercise will tell you which of the three problems is the largest in your specific operation and where the first dollar of attention belongs.

If you want to explore what a structured fuel card program looks like for a fleet of your size and routing profile, that is a conversation worth having before your next program renewal.

Sources

1. Automotive Fleet. Estimated 5-10% of Fleet Dollars Wasted Annually. automotive-fleet.com
2. WEX Inc. Fuel Card Fraud Is on the Rise: How Two-Factor Authentication and Telematics Help Protect Your Trucking Fleet. wexinc.com
3. WEX Inc. Prevent Fleet Card Fraud / Trucking Fuel Theft. wexinc.com
4. Shipley Energy. The Hidden Cost-Per-Mile Problem: How Small Trucking Fleets Overpay on Fuel Without Realizing It. shipleyenergy.com
5. North American Council for Freight Efficiency (NACFE). Idle Reduction. nacfe.org
6. Verizon Connect. 2025 Fleet Technology Trends Report. Survey of 543 fleet managers, 2024. cdn.mediavalet.com
7. Motive. Physical Economy Outlook: Safety, Fraud, Freight, Theft and Retail Trends for Fleets 2025-2026. gomotive.com
8. P-Fleet. Cost-Plus Fuel Cards: A Complete Breakdown for Business Owners. pfleet.com
9. P-Fleet. The Best Fleet Fuel Cards with Discounts in 2026. pfleet.com
10. DispatchTrack. What Does Idling Mean? The Cost of Engine Idling. dispatchtrack.com
11. Business News Daily / GPS Trackit. Tips to Reduce Your Fleet's Idle Time. businessnewsdaily.com
12. American Transportation Research Institute (ATRI). An Analysis of the Operational Costs of Trucking: 2025 Update. truckingresearch.org
13. Millennials Trucking. Cost Per Mile (CPM) for Trucking: How to Calculate It (with Examples). millennialstrucking.com
14. Millennials Trucking. Managing Multiple Fleet Vendors Is Costing You More Than You Think. millennialstrucking.com
15. Millennials Trucking. Why Enterprise Fleets Are Moving to Integrated Fleet Service Models (And What It Saves Them). millennialstrucking.com

Millennials Trucking covers fleet strategy, fuel management, and operations for mid-size and enterprise trucking operations. Have a topic you want us to cover? Reach out.

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