Should I keep my car or buy a new one?

When deciding whether to keep or replace your car, you should factor in reliability, maintenance costs and environmental impact. Our expert reviews and advice can help you to make an informed decision.

Below, we examine your options and consider how the upcoming ban on petrol and diesel, electric vehicle (EV) charging costs and Which? car safety tests might influence your decision.

Plus, learn how the results of our latest car survey will help you to pick a brand you can trust.

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Reasons to keep your car

1. It's running well

At a glance: In our most recent car reliability survey, 16 cars in the 0-4-year age group achieved a full five-star rating.

If you've owned your vehicle for several years and rarely have to deal with breakdowns and faults, congratulations are in order – you might be driving a vehicle that impressed in our annual Which? car survey.

As part of our latest survey, we spoke to more than 50,000 car owners and used their feedback to provide robust reliability ratings for hundreds of vehicles. A total of 16 cars managed a five-star rating in the 0-4-year age group, while nine cars got a dismal one star for 0-4-year reliability.

Which? members get access to all our reliability data. Among the most reliable cars in our survey were a petrol-powered city car with zero recorded breakdowns, plus a Best Buy electric model.

But it's not all good news. One saloon stood out for the wrong reasons – it scored just one star out of five for reliability, and a staggering 40% of owners experienced faults during the survey period.

To see which brands won't let you down, consult our guide on the most reliable cars

2. You don't need (or want) the latest tech

At a glance: Which? survey respondents consider some advanced car tech to be unnecessary.

If you prefer simple car interiors, you'll probably want to avoid newer models that ditch labelled buttons in favour of large touchscreens.

Some of the latest cars we've reviewed are crammed with tech and, while certain features make the vehicle safer, others are more of an annoyance.

Earlier this year, we surveyed Which? members to find out which advanced car tech they find unnecessary.

Of the 1,216 respondents, 56% considered touchscreens unnecessary, 53% said the same for zoned climate control and lane sensors, and 50% for automatic full-beam lights.

From distracting touchscreens to ceaseless beeping sensors: car tech features you could live without

3. You can restore it to showroom condition

At a glance: Our product reviews covering car-cleaning equipment will keep your vehicle pristine.

With the right cleaning supplies, you can transform your car and leave it gleaming. In other words, a deep clean can refresh your vehicle so thoroughly, it can look as good as a new model.

Thanks to our rigorous lab tests, we've uncovered the best pressure washers and best car scratch removers that make light work of stubborn marks and mud-caked wheels. Just remember:

• don't wash your car in direct sunlight – water on your car's bodywork will evaporate quickly and leave ugly water marks
• don't use a car wash – whizzing rollers can cause fine scratches on your paintwork
• don't use washing-up liquid – repeated use will also affect the paint's protective clear coat
• don't rush the job of polishing and waxing – it's a quick ticket to ruining your paint unless you really know what you're doing.

For more cleaning advice, see our guides to the best cleaning sprays and best handheld vacuum cleaners

4. You want to be more sustainable

At a glance: Enlisting the help of a Which? Trusted Trader can help your car last longer

If your old car is running well, don't feel under pressure to replace it.

Any manufacturing process has an environmental impact and that applies to all new cars, regardless of how sustainable their credentials on the road.

Keep your current car running for longer with regular servicing, oil changes and tyre maintenance. When searching for a professional near you to carry out car maintenance tasks, make sure you use a Which? Trusted Trader.

We've independently tested hundreds of models and rounded up the best cars by class – see our guide to the best cars

5. Your car is still viable despite the upcoming ban on petrol and diesel

At a glance: The sale of new petrol and diesel cars is due to be banned in the UK, leading manufacturers to focus on electric or zero-emission vehicles.

The date of the ban was changed from 2030 to 2035 by Rishi Sunak's Conservative government. The new Labour government has pledged to move it back to 2030, although the exact details are not yet widely known.

Confusion about the ban means some drivers might think they need to change their petrol or diesel vehicle for an electric one – but this is not the case.

As the ban only applies to the sale of new cars, as opposed to used ones, it's likely that petrol and diesel cars will remain viable for years to come. There's therefore no need to rush into buying an EV purely because of the upcoming ban on petrol and diesel.

And while those who can charge at home are able to benefit from low charging costs, if you don't have off-street parking you'll be reliant on the public charging network. This is both expensive and, according to a Which? survey  in November 2023, not yet up to scratch. Most respondents (69%) said they were unhappy with the current infrastructure, while only 17% said charge points are reasonably priced. Also, 60% of those who use public chargers experienced a payment issue at least once.

EV owners tell us the best and worst things about owning an electric car

Reasons to change your car

1. Mounting repair bills

At a glance: Fixing recurring problems adds up, so you might prefer to replace your vehicle entirely.

If you’ve been tracking every expense on your car from day one, you might be surprised at how quickly small repairs add up and how these costs tend to increase over time.

We recommend keeping an eye out for recurring issues and being mindful of major maintenance tasks that come with age (including cam belt replacements). If you're struggling to maintain your current vehicle, it might be time to consider a newer alternative.

If you're debating buying a new car, make sure you explore our new and used car reviews before parting with your money

2. Structural rust issues are appearing

At a glance: Rust can compromise a car's safety by damaging critical components including the frame and suspension.

Watch out for structural rust issues, as these can be particularly expensive to repair. 

If you think your car is affected, discuss the issue with a Which? Trusted Trader. Note that, according to the RAC, you can prevent rust by adding a coat of wax to your paintwork.

You can estimate the cost of a service or repair before a mechanic even inspects your car. As long as you have a rough idea of the work needed, websites such as FixMyCar and the RAC Approved Garage Network allow you to get quotes from local garages.

Seven questions to ask before buying a new car: read how to do the necessary checks

3. You want a safer car

At a glance: Newer cars feature advanced driver-assistance systems (ADAS) enhancements, and our expert reviews help you choose wisely.

Modern cars offer greater protection than older models, largely due to features such as ADAS. Standards and testing protocols have advanced over time, meaning a five-star Euro NCAP crash rating from 10 years ago isn't directly comparable with more recent assessments.

To help you choose a vehicle that's truly safe, we test cars more thoroughly than anyone else. In fact, every car we review is subjected to more than 300 individual tests in a lab, on a test track and on real roads.

At Which?, we incorporate crash test results from Euro NCAP, an independent safety organisation we helped to establish in 1997, as a key part of our assessments. These Euro NCAP tests also assess how well cars protect adult and child occupants, as well as pedestrians, in the event of a crash by examining the vehicle's active protection systems.

Revealed: the cars that fail to score highly in Euro NCAP's latest crash tests

4. You want lower refuelling costs

At a glance: Pick the right EV and you'll enjoy low refuelling costs at home, but note that public chargers can be expensive.

EVs can lower your refuelling costs, but this benefit is most effective if you can charge at home. With off-street parking and a home charger, you'll enjoy the cheapest rates available.

While charging at home can cost as little as 7p/kWh, public chargers are significantly more expensive. Ultra-rapid public chargers typically cost around 79p/kWh – that's over 10 times more.

Another option is to swap to a more efficient petrol, diesel or hybrid car – as part of our expert reviews, we measure fuel efficiency for every tested vehicle. Our experts also record cost per mile based on the current month's petrol and diesel cost (taken from RAC Fuel Watch).

See also: How much does it cost to charge an electric car?

5. You’re coming to the end of a finance agreement

At a glance: Making the optional final payment to keep your vehicle might not be the best value for money.

Chances are, the optional final payment to keep your car won’t be good value – although we acknowledge that this isn't always the case.

Still, if you want to dodge a hefty lump sum at the end of your agreement, you could consider trading in your vehicle for a new one – just make sure you opt for a model that's highly rated by owners in our list of the most reliable cars.

Buy a second-hand car at a fair price with our advice on how to buy the best used car, plus see our advice on car finance options

Our expert says:

'Cars are very expensive, but they tend to last far longer than they did 20 or 30 years ago. That’s why it’s important to weigh up the pros and cons if you’re considering changing your car.

'If it's running well and in good condition, there's no need to rush to replace it. But if serious problems develop, your car won't be worth as much as a fault-free model.'

Dino Buratti, Which? cars expert

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