How car modifications affect insurance

Everything you need to know about car modifications and your car insurance.

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If you intend to personalise your car or enhance its performance, you might want to take a look at our guide first. Ultimately, car modifications do affect your car insurance premiums as an insurer is likely to assume your modified car is either more at risk of being involved in an accident or more likely to be stolen. Find out why here.

What are car modifications?

Any change made to a car once it leaves the factory floor is considered to be a car modification.

Car modifications are usually made to enhance the speed, performance or look of a car. Some changes might also help drivers or passengers with disabilities gain better access.

Do car modifications affect car insurance?

When deciding on how much a car costs to insure, an insurance provider will use a group rating system. Each car will be given a rating from 1-50. The cheapest cars to insure will typically have the lowest ratings while those cars that cost the most to insure might have the highest ratings.

This rating is unlikely to change unless there are changes made to a car.

An insurance provider will generally assume that any change made to the engine or body of a car after it leaves the manufacturer can’t be completely guaranteed. And because of this uncertainty, the risk of a modified car being involved in an accident increases, pushing the rating up along with the insurance premiums.

Meanwhile, some modifications can actually increase the value of a car, but unfortunately, these changes might also attract the wrong type of attention from thieves. Insurers could then see your car as being at greater risk of being stolen, which can also increase insurance premiums.

Car modifications that do affect insurance

As each car insurance provider will have its own classifications on modifications, you will always need to check with your own insurance provider to see how it will deal with any planned modifications.

While your car insurance premiums may remain unchanged with one insurer after modifications, another insurer may be unable to cover you if you go ahead with the planned modifications.

Typically, any modification that improves the look, speed or performance of a car is likely to result in higher car insurance premiums. Some of these modifications include:

  • Spoilers
  • Tinted windows
  • Lowered suspension
  • Body kit
  • Upgraded alloy wheels
  • Turbo or supercharged engine
  • Upgraded exhaust
  • Paintwork or body wraps

Car modifications that do not negatively affect insurance

Rather than negatively affect your car insurance premiums, some modifications might actually see your premiums decrease. These could include:

  • Alarms
  • Immobilisers
  • Rear and front parking sensors
  • Tow bar
  • Deeper tread types for winter use

How do I know if my modification will void my car insurance?

The best and simplest way to ensure that a modification won’t invalidate your car insurance is to contact your insurance provider before you make any changes to your car. This way, you can find out whether your insurer is still willing to offer you protection or whether you’ll need to find specialist car cover from somewhere else.

As each insurance provider will have its own guidelines around modifications, contacting your own insurance provider is the only real way of ensuring your protection remains in place at all times.

How to get insurance with a modified car

If you plan on making some smaller, more popular modifications to your car, you may find that standard car insurance is enough protection, as long as you make your insurer aware of exactly what changes you plan on making. If, on the other hand, you can’t get a car insurance quote because the modifications you are planning are quite substantial, it may prove worthwhile to obtain quotes from car insurance providers that deal specifically with modified cars.

Frequently asked questions

*Based on data provided by Consumer Intelligence Ltd, (July ’22). 51% of car insurance customers could save £341.77
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