Two hundred pence. For the first time on record, the average price of a litre of diesel in the UK has passed £2. As reported by Van Fleet World, the average reached a record high of 200.01p at the start of October. RAC analysis in the same report puts the cost of running an average 45mpg diesel car at around 20p per mile, which means a driver covering 10,000 miles a year now spends more than £2,000 on fuel alone.
At that price, the margin for error in fleet fuel spend has all but disappeared. A litre that goes into the wrong vehicle, a fill that exceeds what the tank can hold or a card used by someone other than its named holder costs more than it did eight months ago. Fuel card fraud and everyday misuse were always a drain on fleet budgets. At £2 a litre, they become a material line in the accounts, and fuel card management moves from an administrative task to a financial control.
Why the Cost of Every Unchecked Litre Has Risen
The increase has been rapid. The House of Commons Library recorded average diesel at 199.5p per litre on 5 October 2026, a record, with prices spiking after the outbreak of conflict in the Middle East earlier in the year. Logistics UK's Logistics Report 2026 describes the same conflict as the cause of a sharp rise in fuel costs and warns that fuel price volatility is likely to persist. Fuel duty, held at 52.95p per litre, is also due to rise in January under current government plans, according to a House of Commons Library briefing.
For fleet operators, the implication is simple. Fuel is now the cost where small leaks compound fastest, and fuel management has become a board-level concern rather than a back-office one. A pattern of misuse worth a few hundred pounds a year at 140p becomes a pattern worth considerably more at 200p, without a single extra litre being lost. The same volume of fuel card misuse carries a heavier price.
That changes the economics of control. Checks that once seemed disproportionate to the sums involved now pay for themselves quickly. Losses that would previously have been written off as a cost of doing business deserve a second look, and fuel card management that tests transactions rather than simply paying them is where that second look begins.
Where Fuel Card Fraud and Misuse Hide
Many of the most common fuel card frauds in fleets are unremarkable in appearance. Organised criminals and cloned cards are a genuine risk, yet the everyday version is usually closer to home. Often, it is the misuse of a company fuel card left in a vehicle and used by whichever driver happens to be on shift. It is a fill-up for a partner's car on the way home, paid for on the company account. It is a van filled with premium diesel when standard would do, or a jerry can filled alongside the tank.
None of these transactions looks unusual on a monthly statement. Each is made at an approved forecourt, for a plausible amount, during working hours. The statement reconciles perfectly with the card provider's invoice, and the finance team signs it off. Fuel card management built on statements alone ends there. The problem lies in a question the statement cannot answer: did the fuel go into the vehicle the card belongs to?
Answering that question requires information the card provider does not hold. It needs the vehicle's tank capacity, its fuel type, its mileage since the last fill and its location at the moment of purchase. Fleet fuel management that brings those records together is what allows a transaction to be tested rather than simply accepted. It is also the only reliable way to separate fuel card fraud from honest error, which is why effective fuel card management depends on data the card provider never sees.
Testing Every Transaction Against the Vehicle
A transaction tells you what was bought. The vehicle record tells you whether it was possible. Every reliable approach to fuel card management starts with that comparison.
The first test is volume. A 70-litre tank cannot take 85 litres in a single fill. Where a transaction records more fuel than the vehicle can hold, the excess went somewhere else. The second test is fuel type. Diesel charged to a petrol vehicle, or AdBlue bought for a car that does not use it, signals a card used outside its intended purpose. The third is distance. When fuel purchased over a month far exceeds what the recorded mileage would consume, the gap needs an explanation.
Location adds a further layer, and in fuel card management it is often the deciding evidence. Telematics data shows where the vehicle was when its card was used. A purchase made thirty miles from the vehicle's position, or at three in the morning while it sat at the depot, points to a card being used without the vehicle, which is one of the clearest indicators of fuel card fraud.
Prolius fuel card integration applies these checks automatically. Transactions are cross-referenced against vehicle specifications and live telematics data, and anything that fails is flagged for review rather than buried in a monthly report. Misuse detected within days, rather than discovered at quarter end, limits the loss to a handful of transactions rather than a season of them. That is the difference between a fuel management system that records spend and one that controls it.
Fuel Card Management Across Every Provider
Many fleets hold fleet fuel cards from more than one provider, which complicates fuel card management before a single transaction is reviewed. Some use a bunkered network for HGVs, a universal card for cars and vans and a separate account for public EV charging. Each provider supplies its own statement, in its own format, on its own schedule.
Fragmentation of this kind is where fuel card misuse survives longest. A driver with access to two cards can split purchases between them, and neither provider sees the full picture. Organised fraud, including cloned cards used far from a vehicle's route, exploits the same gaps. Mixed-energy fleets add another dimension, because electricity drawn from public chargers needs the same scrutiny as diesel drawn from a pump.
Consolidating every provider's data into a single dashboard removes that blind spot. Some organisations outsource this to fuel card management services; others bring it in-house through fuel management software that connects directly to each provider. Transactions from each card issuer are standardised and attributed to the correct vehicle and driver, whatever the fuel or energy type. Per-driver efficiency, measured in miles per gallon or watt-hours per mile, becomes comparable across the fleet. A driver whose consumption sits well above colleagues in the same vehicle class stands out, whether the cause is driving style, route or something less innocent.
Book a demo to see how Prolius consolidates multi-provider fuel and charging data in one place.
The Expense Claim Blind Spot
Fleet fuel cards are only part of the picture, and fuel card management that stops at the card leaves a gap. Fuel bought by drivers and reclaimed through expenses, along with mileage claimed in private vehicles, sits outside the card data altogether. Without a structured process, a receipt attached to a claim is often the only evidence reviewed, and receipts are easily duplicated, inflated or padded with non-fuel items.
Higher prices increase the pressure on this channel too. HMRC reviews its advisory fuel rates quarterly, as reported by Fleet News when the current rates took effect on 1 September. When pump prices move faster than the published rates, the gap between what drivers spend and what they reclaim widens, and so does the temptation to make up the difference. Padded claims are fuel fraud by another route, and they deserve the same scrutiny as card transactions.
Connected fuel expense management applies the correct HMRC rate automatically, requires a receipt against every claim and routes each one through a defined approval chain before it reaches payroll. Every claim, approval and rejection is retained in an auditable record. Grey fleet mileage receives the same scrutiny as card transactions, a subject covered in more depth in our article on grey fleet management.
From Detection to Deterrence
Detection limits losses. Deterrence prevents them. The most effective fuel card management controls are the ones drivers know exist.
A clear fuel policy is the foundation of fuel card management and sets the terms: one card per named driver, no shared PINs, standard fuel grades only and immediate reporting of a lost card. Consistent enforcement gives the policy weight. When drivers understand that every transaction is checked against the vehicle it was meant for, the opportunistic misuse that accounts for most losses tends to fall away on its own.
The data then shifts from investigation to planning. Exception reports from fuel card management reveal which depots, vehicle types or card types generate the most anomalies. Fuel spend sits alongside maintenance, fines and accident costs in fleet cost management, giving a true cost per vehicle at a time when every penny per litre is under scrutiny. Well-implemented fleet fuel management systems turn a volatile cost into one the organisation understands in detail.
Get in Touch
Nobody can control the price of diesel. Every fleet can control what happens to the fuel it pays for. At £2 a litre, closing the gaps through which fuel card fraud and misuse pass is one of the fastest ways to protect fleet fuel costs without changing a single route or vehicle. Fuel card management is where that work starts.
Prolius brings fuel card management for every provider into one platform, tests each transaction against the vehicle it was meant for, flags potential fraud for review and connects fuel spend to the wider fleet cost picture.
To find out how it would work for your fleet, contact our team or book a demo.