If you own a 4x4 vehicle, like many other enthusiasts you might like the challenge of customising your ride to gain better performance. But whether you like adapting your vehicle to improve its look or its off-road capabilities, it’s always worth considering how they can impact your insurance coverage.
In this month’s article, we’re going to look at 4x4 modifications and how they can affect your insurance premiums here in the UK. This is intended to be a brief starting point, so we always recommend checking your specific policy terms before carrying out any modifications.

Understanding 4x4 modifications
The definition of a modification for any vehicle, including 4x4s, is an alteration to the original specification and design. Modifications can range from changes to the engine, suspension and wheels to even the body structure itself.
Popular modifications among 4x4 owners include some of the following:
- Engine remapping - In an effort to better performance, some people choose to have their engine remapped, but due to the extra strain this could potentially put on the engine, it could also increase your premium.
- Alloy wheels - As a small modification, your insurer may not increase your premium for alloy wheels, but since they’re easily damaged and targeted by thieves, they will need to know about such a change.
- Suspension upgrades - While suspension can improve off-road capabilities, it may be viewed as a modification that can affect your insurance premium.
- Tow bar - A common addition to 4x4s, adding a tow bar is something you’ll need to declare to your insurance provider.
- Exhaust system upgrades - Upgrading your exhaust system is definitely a modification you need to declare as it alters the performance of the original vehicle.
Impact on Insurance premiums
When you modify your 4x4 vehicle, it is essential to inform your insurance provider about these alterations. Failure to disclose modifications can result in a denied claim or even the cancellation of your policy. Insurance companies need to be aware of modifications as they can significantly impact the risk associated with insuring your vehicle.
The effect on insurance premiums varies depending on the type and extent of the modifications. Generally, modifications that increase the performance or value of the vehicle tend to raise insurance premiums. The rationale behind this is that modified vehicles may have either a higher risk of accidents or theft, leading to increased costs for the insurance provider.
A 4x4s with modifications means it is non-standard, which means a raise in the premium to cover it. If you’re unsure about the potential cost implications of customisations you have in mind, you should consult your provider for guidance. This is the best way to ensure your policy coverage is sufficient for your 4x4.
It should be noted that some insurance providers may allow one or two small alterations, while some modifications might even help to lower your premium — regardless, you should always declare these with your provider.
Policy Terms and Conditions
In addition to potentially higher premiums, modifications can also lead to changes in your insurance policy terms and conditions. Certain modifications may require the addition of specialist coverage or an adjustment to the existing policy. For example, if you install a snorkel or raise the suspension height significantly, your insurance provider may require you to obtain coverage specifically for water crossings or off-road activities.
On top of this, some insurers may have restrictions on the types of modifications they cover. This is especially true for modifications that alter the vehicle’s performance or pose potential safety risks. It is crucial to review your policy carefully to ensure that your modifications are adequately covered and comply with the insurer’s guidelines.
Specialist insurance providers
Given the unique nature of modified 4x4 vehicles, it can be beneficial to seek insurance from specialist providers who understand the intricacies of such modifications. Specialist insurers often have a better understanding of the risks associated with modified vehicles and can offer tailored coverage options that suit your needs.
4x4 modification parts
4x4 modifications can enhance your driving experience and off-road capabilities, but it is important to be aware of their impact on insurance. When modifying your 4x4 vehicle, always inform your insurance provider to ensure your modifications are adequately covered.
Understanding the potential changes to your insurance premiums and policy terms will help you make informed decisions and enjoy your modified 4x4 vehicle with peace of mind. Remember to consult with specialist insurance providers who can provide tailored coverage options for your modified vehicle.
At Milner Off Road, we have a range of parts and components to help you upgrade the performance of your 4x4, whether that’s to enhance the style or off-roading capabilities of the vehicle. Order online today and get same or next-day shipping — we’ve been helping 4x4 owners since 1981 and can deliver your parts wherever you are in the world.