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21 May 2020
Adam Bate

Modified car insurance


A close up of a car exhaust with smoke coming out of it

Many drivers like to improve the way their car looks and performs, and who can blame them? But modifications like these can often impact your insurance.

Alloy wheels, spoilers and souped-up engines can add to the style and performance of your motor, and often increase its value.

But there’s one major drawback to these kinds of modifications: they’re likely to increase the cost of your car insurance.

READ MORE: Is it worth paying more for premium fuel?

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Why modified cars make policies more expensive

When insurers set the price of car insurance policies, they take a number of factors into account. This includes the value of the car they’re covering, its likelihood of being involved in an accident, and its risk of being stolen.

Modifications can have a significant impact on some of these factors.

For example, improvements to your car’s appearance can increase its appeal to thieves. And the higher your insurer considers the risk of theft to be, the higher your premiums will be.

Similarly, if performance modifications you make to your car make it more powerful than the standard model, an insurance company will often consider it more likely to be involved in an accident, and suffer more expensive damage. In both cases, the cost of cover will be increased.

Finally, if the modifications have boosted your car’s value, then the potential cost of replacing it will be higher. This again will be reflected in your policy price.

READ MORE: How car insurance is calculated

Telling your insurer about changes

Car insurance documents with a red toy car on them 

When you get a quote, you’ll be asked if your car has been modified from its original factory condition.

If you don’t mention any changes that could affect a potential insurer’s view of the car, you could end up with invalid cover. Any claim you make could be turned down if the insurer finds out that your car is different to what you stated in your application.

READ MORE: Car engine immobilisers and trackers

Modifications while your policy is in force

If you’re already insured when you make changes to your car, you should tell your insurer. Failing to do so could also lead to your policy being invalidated – it’s not enough to let the insurer know you own a modified car when you come to renew.

READ MORE: How to change your car insurance policy

What changes should you inform your insurer about?

You should tell your insurer about anything that changes your car's value or performance. Many cosmetic modifications also need to be declared eg tinted windows and paintwork. Check with your insurer beforehand and they'll be able to advise you. 

READ MORE: Would you lie to get cheaper car insurance?

Other ways to save

If your modifications have pushed up the cost of your cover, some of these tactics could help to bring it back down:

  • Raise your excess - you can cut your premiums by opting for a larger voluntary excess. So if you agree to pay the first £250 of any claim rather than just the first £100, for example, your policy could cost less. However, it’s worth considering what you could afford if your car did suffer a bump.

  • Beef up your security - if your car is fitted with an alarm or immobiliser, it should be harder to steal. This should lead to lower insurance costs, and additional security should increase these discounts.

  • Add a named driver - young and new drivers will often get more expensive insurance quotes. By adding a more experienced named driver – such as a parent – to your policy, you could see premiums fall.

  • You can find more ways to save in our guide on tips to save on the cost of car insurance.

READ MORE: The excess factor, voluntary excess explained


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