UK insurance with modifications

Aug 11, 2025
9
3
Hey all,

Just wondering how much insurance has been affected with small modifications like splitters, side skirts, wing extender etc. Or is it even worth notifying the insurance about those bits?

Thanks!
 

tracktoy

Committed Cupra 280 Track enthusiast
Staff member
Moderator
Jun 11, 2023
887
726
UK
As with all insurance depends on you, your location and in my experience the number of modifications.

Small number of external bits (splitters etc) normal run of the mill insurance companies are not overly worried about but you reach a point where you need to talk to specialist insurance companies (like adrian flux) and for me personally I have been very happy how little it has cost.

Always declare them because otherwise your are technically not insured in my view.
 
  • Like
Reactions: SRGTD and chux27
Aug 11, 2025
9
3
Yeah I guess I would do a check to make sure they arent going to see them as performance upgrades and hike the price of the insurance up. Was just interested in other peoples experiences. Thanks!
 

Legojon

I only wanted a remap
Staff member
Moderator
Jul 7, 2015
5,084
2,540
I've found most insurances to be pretty good. Including the standard car insurers. I think most a remap has ever cost me is 30-40. If I recall, last time I phoned a standard insurer I tried to explain to them the splitter, diffuser, etc. They just added on "aftermarket bodykit" for 35 for the year.

I've always been nervous about having the mods and not delcaring them. Then after phoning the insurance, wondered why I didn't just do it in the first place.
 
  • Like
Reactions: tracktoy and chux27

SRGTD

Active Member
May 26, 2014
2,773
1,628
Yeah I guess I would do a check to make sure they arent going to see them as performance upgrades and hike the price of the insurance up. Was just interested in other peoples experiences. Thanks!

@chux27 - be aware that non performance upgrades might also result in premium increases - it depends on the insurance company’s approach to risk and whether or not they consider the proposed modifications increase the insurance risk. There isn’t a standard market approach to modifications by the insurance industry, so where one insurance company may require an increased premium another insurance company may not. I’ve fitted non-OEM alloys to my three previous cars; on two occasions, the insurance company I was with didn’t increase my premium but on the third occasion there was a modest premium increase.

With non performance cosmetic modifications, some insurance companies might consider cosmetic upgrades would make a car more of a target for theft as it might be more visually appealing to certain types of scumbags perpetrators who are looking for a ’free’ car 😠. Also, the addition of aftermarket bodywork such as side skirts, splitters and wing extenders can mean accident damage is more costly to repair - i.e. there’ll be additional costs involved in sourcing, painting and fitting the extra non-standard parts compared to the cost of repairing a standard factory spec car without cosmetic upgrades.

As @tracktoy has said, always declare any modifications; pretty much all car insurance policies will have a clause in the small print requiring you to do so and not declaring them could result in your insurance company voiding your policy.
 

Lucas90

Active Member
Dec 3, 2023
45
37
I've added the fact I have made a few cosmetic modifications to my insurance. It only added £15 to my renewal this year and that's for alloys, sideskirts and splitter. Not all insurance companies let you add cosmetic changes to a policy so you may need to shop around. I'm with the AA and it was straight forward.
 

SRGTD

Active Member
May 26, 2014
2,773
1,628
I've added the fact I have made a few cosmetic modifications to my insurance. It only added £15 to my renewal this year and that's for alloys, sideskirts and splitter. Not all insurance companies let you add cosmetic changes to a policy so you may need to shop around. I'm with the AA and it was straight forward.

I think that many insurance companies who don’t allow cosmetic changes might also not allow performance modifications.

Some insurance companies have a range of tiered products at different price points to accommodate different types of customer. Some of those products may allow modifications to be made whereas others might not, so whether or not cosmetic changes are allowed may be down to which insurance product the customer has chosen;
  • the more expensive products in and insurance company’s product range will be the most flexible and have the broadest standard cover with access to call centre staff. These products are likely to allow non-standard changes such as adding vehicle modifications.
  • the lower cost products are likely to be online-only commoditised products with lower levels of standard cover, limited - or no - access to customer support and no scope to make non-standard changes. Any changes that can be made (e.g. vehicle substitution, change of policyholder address etc.) are likely to be processed on a ‘self serve’ basis by the policyholder on the insurance company’s website.
There may intermediate products where the price, scope of cover and what changes can be made sits somewhere between the expensive and low cost products. Anyone buying an insurance company’s internet-only, low(est) cost policy is less likely to be able to add cosmetic or performance modifications.

IMHO anyone who knows they will be wanting to modify their car, it is probably worth using a broker or insurance company that specialises in modified vehicles; they will have staff who understand the modified car market and what specific types of modifications actually are. Some of the large insurance companies whose business is primarily concerned will writing large volumes of standard unmodified vehicles are less likely to have the specialist knowledge needed to accurately assess a modified vehicle risk and / or quote a realistic premium that reflects the risk.
 
Adrian Flux insurance services - discount for forum members.