Think twice before modifying your car

Splashing out on alloy wheels or adding a built-in car phone could see the cost of your car insurance rocket, so always check what impact any modifications will have on your premiums before going ahead.

Research from has found that even small changes to in-car entertainment or navigation systems can dramatically alter the cost of insurance – one motorist, for example, saw their premium rise by 44% after they added a built-in car phone to their vehicle.

The study also found that anyone wishing to add alloy wheels to their vehicles could face a 62% rise in the price of their policy, whilst anyone fitting a body kit could see their premiums rise by over 100%.

Peter Harrison, car insurance expert at, said: “Motorists need to be aware that even making a small modification to a vehicle can dramatically alter the cost the premium you will pay on your insurance.  With premiums potentially costing more than 100 per cent more, motorists should consider whether the modification is really worth the extra insurance expense as well as the cost of the actual work done to modify the car.”

Always declare modifications

Even though you are likely to face higher premiums if you modify your car, don’t be tempted not to declare any changes. You risk invalidating your car insurance altogether if you fail to inform insurers of any modifications or changes to your vehicle, and even the most minor alteration, such as fitting an after market CD player, must be declared when taking out a policy else insurers may reject any future claims.

The insurance Ombudsman has recently received a number of complaints from motorists who have seen insurance claims rejected on the grounds of failing to declare in-car modifications.


One complaint that was upheld was from a motorist that had seen a claim rejected by his insurer because he had not informed them that it had been fitted with a CD changer.

The insurance company claimed that his policy was invalidated because the motorist had failed to disclose a ‘substantial upgrade to the internal entertainment/navigation systems – e.g. satnav unit, games console, CD changer, Bluetooth kit, etc.’

The motorist complained to the Ombudsman on the grounds that the terms of his policy did not make it clear that an upgrade to in-car systems constituted a modification and his complaint was eventually upheld and his policy reinstated.

These case studies highlight the importance of checking the terms and conditions of any insurance policy and also show that it’s not just the addition of alloy wheels or a boot spoiler that are classed as modifications.

Peter Harrison said: “It is essential drivers check the small print of their insurance policy to understand exactly what they are covered for, as many of the more common modifications such as alloy wheels may not be covered in a standard policy. If you do decide to modify your car, check before hand what the cost of cover will be with your insurer and also shop around to see if you can get a better deal on your car insurance elsewhere that covers your modification.”

Make sure you update your circumstances too

Motorists should also be aware that they need to inform their insurers of any changes to their personal circumstances as well as modifications to their vehicle - failure to do so could lead to their policy being invalidated.

It is widely accepted that a change in postcode can lead to a change in premium price but further research by found that a change in job can also have an impact, one example being that a children’s entertainer can expect to pay around 48% more for their car insurance than a teacher.

That is why it is vital that motorists do their research and shop around to find the best value policy to suit their needs to ensure that they are getting the best deal.

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