Modified car insurance

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What is modified car insurance?

Modified car insurance is insurance for cars that have been altered since manufacture. It may cost more to insure a modified car for reasons like increased risk of theft, more expensive parts and a higher likelihood of speed-related accidents.

But there are ways you can look to save on modified car insurance – for example, by cutting down mileage, parking off the road or increasing your excess.

Let’s find out how to insure a modified car and search for the right deal for your needs and budget.

What counts as a car modification?

A modification is any change you make to your car that alters it from the manufacturer’s standard settings.

Modifications tend to fall into two categories: performance or cosmetic.

Performance modifications

Performance car modifications include:

Altering the suspension
Changing the wheels
Increasing horsepower
Turbo upgrades
Re-engineering your engine
Chip tuning and remaps
Intake and exhaust upgrades
Handling modifications
Lowering the suspension
Fuel upgrades
Transmission modifications.

Cosmetic modifications

Cosmetic car modifications include:

Go-faster stripes
Body kit amendments
Sunroof installation
Tinted windows
Specialised paintwork
After-market speaker systems.

What are the most popular types of car modification?

We’ve pulled together some of the most popular modifications:

Engine – changing the engine’s performance can dramatically increase the speed of a vehicle and make it practically a different car in the eyes of an insurance provider.
Wheels – our research reveals that alloy wheels rank as the top car modification, with almost 70,000 alterations recorded across the UK.
Tinted windows – as long as they’re the right side of the legal limits, changing the windows shouldn’t impact too highly on your insurance. Tinted windows may even be considered a crime deterrent by some insurance providers.
Stickers – even a sticker could be classed as a modification. In one case that was reported by the BBC, a vicar in Wales was warned by her insurance provider that the religious messages she had stuck to her car could invalidate her insurance policy because they hadn’t been declared.
Bodywork – making changes to the body of the car can increase its value and will need to be declared as soon as installed. They could also affect aerodynamics and safety in the event of an accident.
Spoilers – a good spoiler will improve handling when travelling at high speeds. But it also increases the chances of speeding. If you do fit a new spoiler, ensure it doesn’t block the view from the rear window and is fitted securely by a qualified mechanic.
Parking sensors – these are designed to reduce the risk of minor bumps, which account for the vast majority of claims. This type of modification could mean you’re seen as a safety-first driver, which may reduce your premiums.
Exhaust – changing the exhaust system could enhance the performance of the car. Any changes to the original performance can affect the speed of your car, which insurance providers may see as a risk.

Some cars can also be modified to make them easier to use for drivers with disabilities. For example:

Wheelchair ramps and lifts
Altered foot pedals
Hand controls
Steering aids.

Under the Disability Discrimination Act 2005, it’s illegal for insurance providers to charge disabled drivers more for their car insurance. However, if some modifications are expensive to repair or hard to replace, premiums may be higher to reflect these.

How much does modified car insurance cost?

The cost of your modified car insurance isn’t just based on your car. The price you’ll pay also depends on your individual circumstances including:

Your age
Where you live
Your job
Your driving history, including any no-claims discounts, driving offences or previous claims.

All modifications, no matter how minor, have the potential to affect the cost of your car insurance. In many instances, car modifications could lead to higher premiums. But shopping around could help you find a cheaper quote.

Why does it cost more to insure a modified car?

The cost of your insurance premium is based on the probability of you making a claim. So, when it comes to modifications, insurance providers will consider the following factors:

Increased value – if the modifications increase the value of your car, any claims you make could be higher as it may now be more expensive to repair or replace parts
Increased performance – if you’ve made your car faster, that could increase the risk of you being involved in a speed-related accident
Theft risk – your car may be at greater risk of theft and vandalism, especially if you’ve had expensive tech installed or you’ve modified its performance
Vehicle integrity – insurance providers could assume that any modifications that alter the manufacturer’s standard settings can’t be guaranteed and may affect the car’s integrity
Young drivers – 17 to 24-year-olds are statistically more likely to claim on their insurance, so any modifications could raise their premium even more.

Check with your provider before you alter your car, to see how it’s likely to affect your premium.

What does modified car insurance cover?

Insurance for modified cars will cover you for the same risks as any other car insurance policy. You’ll have three levels of cover to choose from:

Third-party – the minimum level of cover you need to legally drive in the UK. It covers injuries to third parties and damage to their property. It won’t cover your own car.
Third-party, fire and theft – includes third-party cover plus cover against fire, damage or theft of your own vehicle.
Comprehensive – the highest level of cover. It includes third-party, fire and theft cover as well as damage to your own car, even if you’re at fault.

Optional extras for modified cars

You can also take out the usual optional extras with your modified car insurance. For example:

Breakdown cover – recovery and assistance if your modified car breaks down on the road or at home
Courtesy car – a temporary replacement vehicle if your modified car is in for repairs following an accident
Key cover – could cover replacement and reprogramming of keys or fob if they’re lost or stolen
Windscreen cover – could cover the cost of repairing or replacing a damaged windscreen
No-claims protection – protects your no-claims discount so you won’t lose it in the event of a claim.

Optional extras could increase the cost of your premium, so think carefully about adding additional cover that you may not need.

What modifications could help lower my car insurance?

Here are some modifications that could lower your premium:

Parking sensors – these can lower the risk of minor bumps.
Security measures – by fitting an immobiliser or tracking device, potential thieves could be discouraged.
Tow bar – if you use your car for towing a caravan, horse box or trailer, you’re likely to drive more slowly and carefully, so a tow bar could lower your premium. Then again, insurance providers might also consider towing to be an added risk. So, it’s worth checking with your provider before you get one fitted.
Sway bars – also known as anti-roll or stabiliser bars, these can help you distribute the car’s weight evenly and reduce body roll when turning or swerving.

Do I have to tell my insurance provider about modifications to my car?

Yes, by law you must tell your insurance provider about any modifications to your car, even if you didn’t make the changes yourself.

If you don’t disclose modifications, it could invalidate your car insurance. This means you could be driving without insurance, which is illegal.

When you speak to your insurance provider, let them know:

About all modifications, even minor ones
Details about the modifications including cost and who fitted them (keep all receipts and records of the modifications)
About any modifications you wish to make.

While you should be able to insure a modified car quite easily, you need to make sure that your modifications are legal. If any of them break the law, you won’t be able to get cover at all.

Some common examples of illegal modifications include:

Neon lights fitted under the car
Overly tinted windows (they must let in at least 70%-75% of light)
Excessively loud exhausts (they mustn’t exceed 74 decibels).

How can I save on modified car insurance?

It might not always be easy to get cheap modified car insurance, but there are possible ways of reducing the cost of your car insurance premium, whatever type of car you have.

For example, you might get cheaper modified car insurance by:

Cutting down on your annual mileage
Parking overnight in a secure place
Increasing your voluntary excess.

If you want to know how any particular modification will affect your insurance, check with your insurance provider.

And if you’re still keen on modifying your car, our comparison service lets you declare the changes you’ve made up front. So, you know the price you’re offered will include any modification you’ve made.

Compare car insurance quotes today and see what deals are available for modified cars.

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What do I need to get a quote?

To compare quotes with us, you’ll need to give us some details about your car including:

Your registration
Your no-claims discount
Any additional drivers you want to include on your policy.

We’ll also need a few personal details, like your age, address and occupation. If you’ve compared with us before, we’ll fill those in for you. We’ll then show you a list of quotes to compare.

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What our expert says...

“Always be sure to make your insurance provider aware of any modifications as these could affect your premium. And remember, not all modifications will increase the cost of your car insurance. For example, modifications that enhance your car’s safety or security may even reduce your premium.”

- Julie Daniels, Motor insurance expert

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Frequently asked questions

What if my car comes with modifications?

If you’ve bought your new car from an authorised dealer and opted for extra features, such as alloy wheels, it shouldn’t affect your premium too much. This is because they’ll have been fitted according to the manufacturer’s specifications.

However, if the modifications increase the value of your car, you may pay a slightly higher premium than you would for the basic model.

If you’re buying a second-hand vehicle that’s been modified, make sure you get all the details of the modification and pass them to your insurance provider.

Can you make modifications mid-policy?

Yes, you can make modifications to your car mid-policy.

Just be sure to notify your insurance provider of any new modifications as soon as possible. Don’t wait until it’s time to renew. If you neglect to inform them and you need to make a claim, your policy could be invalidated.

Be aware that your premiums could increase as a result of the modifications, so it’s worth weighing this up before deciding to make them.

How is the value of a modified car calculated?

Considering how varied modifications can be, there’s no straightforward way to calculate a modified car’s value.

This is why most modified car owners take out an agreed-value policy with their chosen insurance provider. It means that you and your provider agree on an amount they’ll pay out if your car is written off, regardless of its original market value.

Will I need specialist modified car insurance?

Most mainstream insurance providers should be able to cover basic modifications. But heavily modified vehicles may need specialist modified car insurance.