What Car Modifications Affect Insurance?

If you’re looking to insure your modified car, it can seem like there’s a lot to understand, especially when it comes to what car modifications have an impact on insurance.

A modified car is a vehicle that has been altered from factory standard; this can range from stickers to body kits, lowering and remaps. While some modifications have no impact on your insurance premium, some can increase them. Knowing how your modifications will affect your insurance premiums can be confusing.

Here at Advance Insurance, we want to make the whole process as stress-free and straightforward as possible. That’s why we’ve put together a guide on exactly that!

We are specialists in modified car insurance, so with our advice, you can feel a little more clued up on the right cover you need.

What Modifications May Raise The Cost Of Your Car Insurance Premiums?

Car modifications will fall into two categories; to enhance your vehicle’s performance and appearance.

Engine & Mechanics

If you modify your engine or the vehicle’s mechanics such as making exhaust system changes, or transmission or air filter modifications, you need to declare this to your insurance provider. This is also the case if you add a turbo or supercharger to your car.

Wheel Modifications

Making modifications to your wheels can alter the handling of your car, and also incrfease its overall value. Therefore, if you are fitting either bigger wheels or wider tyres, or you’re fitting alloy wheels, you need to declare these modifications.


Many various different bodywork modifications can alter your insurance costs, including but not limited to:

  • Flared arches,
  • Spoilers,
  • Side Skirts,
  • Front & Rear Lips,
  • Tinted Windows,
  • Light changes.

Brakes and Suspension

If you are looking to up-rate your brakes or lower your car, this will have an effect on its behaviour on the road, therefore notifiying your insurance provider of these changes is vital.


Many car insurance companies will consider stickers and decals as car modifications. If you’re thinking of applying them, make sure to check with your insurance provider beforehand to be sure that they accept these modifications as part of their policy.

Illegal modifications include neon lights and overly tinted windows – as these break the law, they cannot be covered at all.

What May Not Affect Your Car Insurance?

Before we discuss modifications that may not affect your insurance, it’s vital to note that you must check with your insurance provider before any changes are made to your vehicle. Whether or not these changes affect your car insurance will be down to the insurance company your policy is with.

Dash Cams

If you have a dash cam fitted to your car to provice additional evidence should you have to make an insurance claim, some insurers will favour this.

Parking Sensors

Did you know that 20% of car insurance claims come from accidents in car parks? Parking sensors can really help avoid parking prangs and manoeuvre in and out of tight spaces.

Tracking Devices

Tracking devices can help authorities to track down your car should it be stolen.

Tow Bars

Did you know that a tow bar is technically a modification if your car didn’t come with one as factory standard?

You should let your insurer know if you are fitting a tow bar.

What Car Modifications Have To Be Declared?

If you are planning to modify your car, it’s vital that you inform your insurance provider of every change you make.

Enhancing your car’s performance and aesthetics can make it more susceptible to accidents and theft.

If you don’t declare your modifications you risk invalidating your insurance, and if you do invalidate your insurance policy, you will be driving your car illegally. This also means that your claim will be refused when you need financial protection.

Can Modifications Be Added Mid Policy?

Some insurance providers will be more than happy to add modifications mid-policy. At the end of the day, many modified cars are ongoing projects!

It’s important to note that you should check with your insurance provider as to how the changes you have planned will affect your premium before you add them to the car.

Get Yourself Covered Today With Modified Car Insurance Specialists

If you are looking for specialist modified car insurance to make sure that you have the right car insurance coverage, get in touch with Advance Insurance today.

Choosing a specialist-modified car insurance policy over a standard car insurance policy will mean that your car is covered by a policy designed and tailored for modified vehicles.


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