What lowers a car's value most?
Some things that lower a car's value are out of your hands, like age. Others, like a missing service or a scruffy interior, you can often fix before you sell. Here's what moves used car prices most, using typical asking prices from more than 93,000 UK adverts in the Valu8 database (November 2026).
Each comparison below is like for like: the same make and model, and the same year unless it says otherwise. They are typical patterns across many cars, not a rule for any one car.
1. Age
Every year counts. Comparing the same model one year apart, the older car was typically advertised for about 12% less.
| Car age | Typical drop for each extra year |
|---|---|
| 2018 and newer | about 9% |
| 2010 to 2014 | about 16% |
| All years from 2010 | about 12% |
You can't change your car's age, but it's a reason not to wait too long once you've decided to sell.
2. Mileage
Mileage is the biggest factor you can see in the data after age.
| Mileage (same model and year) | Typical asking price |
|---|---|
| 40,000 to 80,000 miles vs under 40,000 | about 17% lower |
| Over 80,000 vs 40,000 to 80,000 | about 29% lower |
| Over 80,000 vs under 40,000 | about 39% lower |
A 2017 Volkswagen Golf, for example, was typically advertised for about £11,250 with under 40,000 miles and £8,000 with over 80,000 miles. See 2017 Volkswagen Golf asking prices.
What buyers care about is mileage for the age, and whether the MOT record shows it rising steadily. A drop in recorded mileage, or a long gap with no MOT, will cost you more than a few extra thousand miles.
3. Condition and MOT history
These don't show up as a single number, because every car is different, but they are the main reason two cars of the same age and mileage are priced differently. The items that cost sellers most are:
- Repeat MOT advisories that were never fixed, especially corrosion, brakes, tyres and suspension
- Missing service history, or a long gap between services
- Visible damage: dents, scratches, kerbed alloys and worn seats
- Warning lights on the dashboard
Cheap fixes are often worth doing before you sell: tyres near the limit, a missing service, bulbs and wipers, and a proper clean. Expensive structural work often isn't, so price it honestly and say so in the advert. Our guide to MOT advisories and car value goes into more detail.
4. Fuel type
For the same model and year, diesel versions were typically advertised for about 14% less than petrol versions in our data. Demand has shifted towards petrol, hybrid and electric cars, and clean air zones matter to buyers in some cities.
5. Gearbox and spec
Automatics were typically advertised for about 30% more than manuals of the same model and year. Part of that is because automatics often come with bigger engines and higher trims, so it isn't a pure gearbox effect. The point for sellers is to list your exact trim, engine and gearbox clearly, because buyers search for them.
6. Who you sell to
Where you sell changes the price as much as anything about the car. Private adverts were typically about 30% below dealer adverts for the same model, year and mileage band, and a part-exchange offer is usually lower again. See private sale vs dealer prices.
What you can do
- Sell sooner rather than later once you've decided
- Keep the MOT record tidy: fix advisories that are cheap to fix
- Gather the service book, invoices, V5C and both keys
- Clean the car properly and take clear photos in daylight
- Describe the exact trim, engine and gearbox in the advert
Check what buyers will see first. A free Valu8 valuation shows a private sale estimate and your official DVSA MOT history, advisories and mileage record.
FAQs
What lowers a car's value the most?
Age and mileage are the biggest factors in the advert data. For the same model and year, cars over 80,000 miles were typically advertised about 39% below those under 40,000 miles.
How much value does a car lose each year?
Comparing the same model one year apart, the older car was typically advertised for about 12% less in our data: about 9% for 2018 and newer cars and about 16% for 2010 to 2014 cars.
Do diesel cars lose more value?
In our data, diesel versions were typically advertised for about 14% less than petrol versions of the same model and year.
Does Valu8 buy cars?
No. We don't buy, sell or broker cars. All figures are estimates, not offers.