What Is High Mileage for a Used Car? UK Averages

There is no single number that turns a used car into a high mileage car. The honest benchmark is the average, and the biggest public source of it is the DVSA MOT anonymised data set. Across 31.2 million initial class 4 tests, cars record roughly 7,145 miles a year. Multiply a car's age by about 7,000 and you have the normal figure for it.

Quick answer

High mileage means clearly more than about 7,000 miles for every year the car has been on the road. A three year old car on 45,000 miles is high. A ten year old car on 71,000 miles is bang average. What matters far more than the total is how those miles were covered, whether the car was maintained, and whether the number on the dashboard matches the number recorded at every MOT.

Roughly what to expect by age

Treat the low and high columns as rules of thumb built around that 7,145 mile average, not as hard limits. Plenty of good cars sit outside them in both directions.

Why low mileage deserves more suspicion than high

Buyers reward a small number, which is exactly why a small number is worth more scrutiny than a big one.

Start with the mechanical side. Cars dislike standing still and dislike short cold journeys. A car that has covered 20,000 miles in ten years has usually done them two miles at a time, from cold, to a supermarket and back. Brake discs corrode and pit, tyres age out long before the tread runs low, fluids degrade on a calendar rather than an odometer, rubber hoses and seals harden, and a diesel particulate filter never gets hot enough to clear itself properly. A cambelt has a time interval as well as a mileage interval, and on a garage queen it is the years that expire first.

Then there is the obvious point. The odometer reading is the single easiest thing on a car to change. Mileage correction is sold openly as a service, the equipment plugs into the diagnostic port, and the job takes minutes. Nothing on the car itself will tell you it has happened.

The MOT trail is what exposes clocking

Every MOT test records the odometer reading on the day of the test. From the car's third birthday onwards that produces an unbroken line of readings, and it is the one part of a car's history a seller cannot rewrite. A clocked car shows up as a reading that goes backwards, or as one year with an implausibly small jump wedged between two normal ones. You can read the raw test list free on GOV.UK, and a full mileage check sets every recorded reading out in order, works out the annual pattern and flags discrepancies against the current advertised figure.

Three limits are worth knowing before you rely on it.

• No trail for the first three years: the first MOT is due at three years, so a nearly new car has no recorded readings to compare at all.
• Gaps between tests: a car can be clocked, sold and put back before the next test. A single year with a jump far out of line with the rest deserves a question, in either direction.
• Older cars: digital records do not stretch back through the whole life of a very old car, so the earliest years may simply be missing.

The MOT history is worth reading for more than the numbers. Advisories tell you where the car is wearing, and corrosion notes on a high mileage motorway car matter more than the mileage itself.

Motorway miles are not town miles

Two cars can show the same reading and be in completely different condition. A rep's diesel that did 25,000 miles a year in long motorway runs spent most of its life warm, with the engine at a steady load, few cold starts, little clutch work and gentle braking. A city car that did 6,000 miles a year in school runs spent its life warming up and cooling down, with the clutch worked constantly and the brakes never drying out.

So ask what the miles were. A single owner with a long commute is a good story. Seven owners in four years, with the mileage climbing in bursts, is a different one, and the ownership record will show you which you are dealing with. Be aware of what a history check cannot tell you here. It does not include service records, and it does not include taxi or private hire licensing, so a former minicab will not announce itself. Ask for invoices and look at the wear.

What high mileage actually costs

The risk with distance is not that the engine will suddenly fail. It is that a queue of jobs arrives at once, and on a cheap car any one of them can be worth more than the car.

• Cambelt and water pump, if the interval has not been done and there is no invoice to prove it.
• Clutch and, on many modern cars, the dual mass flywheel behind it.
• Suspension bushes, top mounts, dampers and drop links, which are what makes a high mileage car feel tired.
• Diesel particulate filter, EGR valve and turbo on a diesel used mostly around town.
• Automatic gearbox fluid, which many owners never touch because the maker called it sealed for life.
• Corrosion on the subframe, brake pipes and sills, which is age driven rather than mileage driven.

There are ownership costs too. Manufacturer warranties run out on mileage as well as years, some extended warranties refuse cars above a mileage ceiling, and the next buyer will look at the number the same way you are looking at it now.

So is 100,000 miles too much?

Not on its own. A well maintained car that reached 100,000 miles in eight years of steady driving is usually a better buy than the same car that took fifteen years to reach 40,000 miles in short hops. Judge the evidence rather than the number.

• The mileage rises at a consistent rate across the MOT record, with no reversal or suspicious flat year.
• Big interval jobs have invoices, not just a story.
• MOT advisories show ordinary wear rather than repeated corrosion warnings.
• Ownership history is short and stable rather than a chain of quick flips.
• The car drives without smoke, without warning lights and without a slipping clutch on a cold start.

Some engines and gearboxes cope with distance far better than others, and the gap between models is wider than the gap between 80,000 and 120,000 miles on the same car. Our car comparisons and used car model pages are the place to see how a specific model behaves as the miles pile up before you commit to one.