More About Modification
What Counts as a Modified Car?
Any vehicle that differs from its original manufacturer's specification is considered a modified car by UK insurers. Modifications fall into two broad categories: cosmetic modifications, which change the appearance of the car, and performance modifications, which affect how the car drives. Both types must be declared to your insurer, regardless of how minor they may seem.
Common cosmetic modifications include alloy wheels, body kits, spoilers, lowered suspension, tinted windows, custom paintwork, vinyl wraps, and upgraded interior trim. Common performance modifications include engine remaps and ECU tuning, turbocharger or supercharger installations, air filter and induction kit upgrades, performance exhaust systems, uprated brakes, and gearbox or drivetrain changes.
Even modifications you might consider standard, such as fitting aftermarket alloys or adding a roof rack, need to be declared. Failing to disclose a modification at the point of taking out a policy can invalidate your insurance entirely, leaving you uninsured in the event of a claim. If you are ever unsure whether something counts as a modification, the answer is always to declare it and let the underwriter make the assessment.
How Modifications Affect Your Premium
Not every modification will increase your premium, and some may have no effect at all. The impact depends on the type of modification, its effect on the car's value, performance, repairability, and theft risk.
Cosmetic modifications such as alloy wheels or a body kit may increase the car's value and therefore the cost of replacement in a claim — but they do not necessarily affect how the car performs on the road. Performance modifications such as engine remaps, forced induction, or suspension upgrades alter how the car behaves dynamically, which changes the risk profile in the eyes of an underwriter.
Because Performance Direct searches a panel of leading UK underwriters rather than applying a blanket loading, your modification is assessed on its individual merits. In many cases, particularly for cosmetic or mild performance upgrades, modifications make no difference to the price of your policy at all. Where a modification does affect the premium, we work to ensure the adjustment reflects the actual change in risk — not a catch-all surcharge applied to anyone whose car differs from factory standard.
The Importance of Agreed Value Cover
Standard car insurance pays out the current market value of a vehicle at the time of a total loss claim. For a modified car, this creates a significant problem. The market value of a modified car rarely reflects the true cost of the vehicle, because the modifications themselves, the labour, the specialist parts, and the time invested in the build, are rarely captured in standard valuation tools.
Agreed value cover resolves this by fixing a mutually confirmed value for the car at the start of the policy. In the event of a write-off or total loss, that agreed amount is paid — not an open market valuation that fails to account for what your car is actually worth. For modified car owners who have invested substantially in their vehicle, agreed value cover is worth discussing when arranging your policy. Ask us about agreed value options when you request your quote.
Legal and Illegal Modifications
Some modifications are prohibited under UK law and cannot be covered under any insurance policy. These include excessively loud exhausts exceeding the legal noise limit, suspension lowered to a point where it affects headlight alignment and dazzles other road users, changes to the colour of headlights or rear lights, the use of neon underglow lighting visible to other drivers, and any modification that affects the vehicle's type approval. Performance Direct can only insure modifications that are legal under UK road traffic legislation. If you are unsure whether a planned modification is legal, we recommend checking with the DVLA before proceeding.
Get a Modified Car Insurance Quote
Performance Direct has been arranging insurance for modified cars since 1995, as part of the Grove and Dean Group, Chartered Insurance Brokers since 1974. Our panel of leading UK underwriters includes specialists who genuinely understand modified vehicles and assess them on their individual specifications, not on a generic modified car rate. Whether your car has a single cosmetic change or has been extensively rebuilt, get a quote online or call our team directly. We are available six days a week and our online quote engine is available around the clock.
