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Modified car insurance

Many drivers like to improve the way their vehicle looks and performs. Alloy wheels, spoilers, kit cars and souped-up engines can all increase your enjoyment of your car, and often also its value.
But there is one major drawback to these kinds of modifications: they are likely to increase the cost of insurance.

Why modifications make policies more expensive

When insurers set the price of motor policies, they take a number of factors into account, such as the value of the car they’re covering, how likely it is to be involved in and accident, and what the risk is of it being stolen. Modifications can have a significant impact on some of these factors. For example, improvements to your vehicle’s appearance can increase its attractiveness to thieves: the higher your insurer considers the risk of theft to be, the higher your premiums are. Equally, if your car is more powerful, it could be thought more likely to be involved in an accident. Or, any accident it is involved in could cause more 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 – if it is stolen, written off in an accident, or destroyed in a fire – will be higher. This again should be reflected in your policy price.

Telling your insurer or broker about changes

When you compare car insurance prices, you’ll be asked on your application form if your vehicle has been modified from its original or factory condition. If you don’t mention any changes that could affect a potential insurer’s view of the vehicle, you could end up with cover that is invalid. 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.

Modifications while your policy is in force

If you already have car insurance when you make changes to your vehicle, you should inform your provider. Failing to do so could also lead to your policy being invalidated – it’s not enough to let the insurer know when you come to renew.

What changes should you inform your insurer about?

Your insurer doesn’t want to know about every little change you make. If you have a new paint job, for example, that’s probably not going to affect your car’s performance or value greatly, so there is no reason to tell your provider. You should bear in mind the factors listed above: if the modification could have an effect on performance, engine size, value of the car, or its liability to being stolen, then let your insurer know. If in doubt, you should give the provider a call to check. After all, if it’s not a relevant change, you won’t be charged extra. And if the modification does affect your cover, then you would have risked driving with an invalid policy if you hadn’t come clean.

Other ways to save

If your modifications have pushed up the cost of cover, you may be able to use other tactics to bring it back down.Here are a few to consider:

  • Reduce the excess you pay. 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, your policy will cost less.
  • Beef up your security. If your car is fitted with an alarm or immobiliser, it should be harder to steal. This should lead to a lower cost of cover.
  • Add a named driver. If you are relatively inexperienced on the roads, this is probably making your insurance more expensive. By adding a more experienced named driver, such as a parent, to the policy, you could see premiums fall.
  • Shop around: As you’re on already, you probably don’t need reminding. But if you’re buying insurance for the first time, or your policy is up for renewal, comparing the best prices from the widest range of providers is the easiest way to cut your premiums.


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