Most excess mileage bills are written long before the driver ever goes over. They’re written the moment someone picks a round number on a quote, doesn’t think about it too hard, and signs.
Three or four years later, the car goes back, the funder runs the numbers, and an invoice arrives that nobody budgeted for. It’s one of the most common, and most avoidable, frustrations in business leasing.
Here’s how we work through mileage with the businesses we look after, so the figure on your contract reflects what your drivers actually do, not what you hoped they’d do.
Why this small number causes such big bills
Every lease is priced around a total mileage figure. A car leased for three years at 10,000 miles a year is priced on the assumption it’ll come back with 30,000 on the clock. Go over, and the vehicle is worth less at hand-back. The excess mileage charge is the funder recovering that difference.
Charges are quoted in pence per mile, and they vary by vehicle and by funder. On a modest hatchback, the rate might be bearable. On a premium SUV or a high-spec EV, it can be brutal. We’ve seen final invoices comfortably into four figures, and the conversation that follows is never a happy one.
The reason this catches people out is simple. Excess mileage is almost always charged at a higher pence-per-mile rate than the equivalent miles would have cost to include in the lease at the outset. You save a few pounds a month by under-declaring. You pay it all back, with interest, at the end. If the way leasing prices are built up is new to you, our guide to how leasing pricing actually works lays out the mechanics.
Start with what the driver actually does
A sensible mileage figure starts with three questions:
- What does this driver actually do in this vehicle? Not what they think they do. What does a real week look like, including weekends and holidays?
- How has that changed? Hybrid working, a wider patch, a growing client base, the school run added in. Driving habits drift, almost always upwards.
- How long is the contract? A 36-month lease leaves less room for surprises than a 48-month one. The longer the term, the more conservative your estimate needs to be.
If you have telematics, MOT history, or fuel card data from the existing car, use them. The odometer on the vehicle you’re replacing, divided by the years you’ve had it, gives you a far better baseline than a gut feel.
Then add a buffer. Ten to fifteen per cent on top of your honest estimate is sensible for most drivers. It costs a little more each month, and it gives you headroom for a busier year, a holiday trip, or a change in role. Think of it the way you’d think about insurance. Under-cover yourself to save a few pounds, and the saving disappears the first time you actually need the cover.
Worked example: the sales rep doing around 20,000 miles a year
Take a common scenario. Your sales rep covers the South of England, drives to client sites four days a week, and put 19,500 miles on the clock last year. You’re replacing the car on a 36-month lease.
The obvious answer is to lease at 20,000 miles a year. The better answer is somewhere between 22,000 and 23,000, and here’s why.
Sales territories rarely shrink. If anything, they grow. A single new account in the wrong postcode can add 2,000 miles a year on its own. Three years is a long time, and ‘19,500’ tends to look optimistic by year three.
The difference in monthly rental between 20,000 and 23,000 miles is usually modest. The difference at hand-back, if the driver does 24,000 a year and you only paid for 20,000, is anything but. Nine thousand miles of excess, at a typical excess rate, lands as a serious invoice.
Worked example: the office manager doing around 8,000 miles a year
Now the opposite end. Your office manager has a small hatchback as a company perk, lives ten minutes from work, and does a low-mileage commute plus weekends. Around 7,500 to 8,000 miles a year.
The instinct here is to match the lease tightly to the mileage and lock in the lowest rental. We’d still nudge you to 9,000 or 10,000 miles a year, for two reasons.
The first is that life changes. A house move, a new partner who lives further away, a parent who needs more frequent visits. Any one of these can add a few thousand miles a year, quietly. Low-mileage contracts have very little tolerance, and 1,500 extra miles a year across a three-year term is still 4,500 miles of excess at the end.
The second is that the cost step from 8,000 to 10,000 on a small car is usually pennies in monthly terms. The protection it buys is disproportionate to what it costs.
The bigger mistake at this end of the scale is going too far the other way and leasing at 15,000 ‘to be safe’. There’s no refund for unused miles. Over-pricing the risk is just money walking out of the door.
A quick reference for sense-checking your number
| Driver type | Honest annual estimate | Suggested lease allowance | Why the buffer matters |
|---|---|---|---|
| Office-based, short commute | 7,000 to 9,000 | 10,000 | Life changes, weekends, holidays |
| Mixed business and personal | 10,000 to 14,000 | 12,000 to 15,000 | New roles, growing client list |
| Field sales, regional | 18,000 to 22,000 | 22,000 to 25,000 | Territory creep, account changes |
| National sales, heavy travel | 25,000 to 30,000 plus | 30,000 plus, with a careful conversation | Excess rates bite hard at this level |
These are starting points, not rules. The right number depends on your contract length, the vehicle, the funder, and the driver. It’s the kind of detail we work through with you properly before anything goes to quote.
What to do if mileage is drifting mid-contract
The single most useful habit you can build is a yearly mileage check across your fleet. Ten minutes per car, once a year. If a driver is on track to overshoot, you usually have options.
Some funders will let you adjust the contract mileage mid-term in exchange for a revised rental. It’s not always possible, and it’s not always worth doing, but knowing in year two beats finding out at hand-back. We’ll dig into this in our upcoming piece on end-of-lease returns, alongside the related question of how to choose the right contract length. Both decisions feed straight back into mileage.
The three mileage mistakes we see most often
Looking back across the businesses we’ve worked with, the same three errors come up again and again.
The first is guessing. No look at the existing odometer, no thought about how the role has changed, just a round number picked from the air.
The second is optimism. ‘He’ll be in the office more next year.’ He won’t. And if he is, the next person in the seat probably won’t be.
The third is using mileage as a price lever. Trimming the figure to bring the monthly rental down to a target. It works on paper, and it fails at the end of the contract.
None of these are foolish mistakes. They’re what happens when a busy owner has ten other things on, is being pushed to sign, and is looking at quotes that all blur into each other. It’s exactly the sort of decision a broker should be slowing down and talking through with you properly, not nodding past on the way to a signature.
How we approach it
We deliberately work with a small number of businesses, usually with one to twenty vehicles, so we can actually get to know how each driver uses their car or van. That changes the mileage conversation from a tick-box to a proper sense-check.
When we’re building a quote for business car leasing, we’ll ask about each driver’s role and routine, look at the existing vehicle’s mileage history if you have it, and pressure-test the figure before it goes anywhere near a funder. If your fleet is mixed, perhaps a couple of electric cars for the directors and some vans for the team, we’ll think about each vehicle on its own terms rather than applying one number across the board.
It’s an unglamorous part of the job. It’s also the part that decides whether your end-of-contract experience is a non-event or an awkward phone call.
Before you sign, run through this
- Have you checked the current vehicle’s actual annual mileage, not your impression of it?
- Have you thought about how the driver’s role might change over the contract term?
- Have you added a buffer of around ten to fifteen per cent?
- Do you know the excess mileage rate quoted on the contract, in pence per mile?
- Have you planned a yearly check-in to catch drift early?
Five ticks puts you ahead of most of the businesses signing leases this month.
If you’d like a proper conversation about it
Mileage looks like a small line on a quote, and behaves like a meaningful chunk of the real cost when it goes wrong. If you have a vehicle coming up for renewal, or you’re adding one or two to the road, we’re happy to look at the numbers with you and make sure the figure on the contract reflects how the car will genuinely be used.
You can read a bit more about how we work, or just pick up the phone. A ten-minute chat now beats an unexpected invoice in three years’ time.
