The areas of the UK with the highest proportion of illegal car modifications have been revealed, with Gloucestershire topping the list.
The county with a population of 637,100 saw 925 offences in 2020 - equivalent to 1,452 per million people. Norfolk, where 907,800 people live, saw 1,127 offences - equivalent to 1,241 per million people, placing it second on the list. Third was Northern Ireland, with 1,179 per million people.
Rank |
Area |
Total offences |
Offences per million people |
1 |
Gloucestershire |
925 |
1,452 |
2 |
Norfolk |
1,136 |
1,251 |
3 |
Northern Ireland |
2,232 |
1,179 |
4 |
Suffolk |
873 |
1,147 |
5 |
London |
9,373 |
1,047 |
6 |
Surrey |
930 |
777 |
7 |
Northamptonshire |
501 |
665 |
8 |
Dyfed-Powys |
320 |
616 |
9 |
Greater Manchester |
1,518 |
535 |
10 |
Leicestershire |
494 |
449 |
Data from 36 UK police forces acquired by Compare the Market via a freedom of information request placed Gwent at the bottom of the list. The Welsh county, with its population of 594,200, saw only four illegal car modifications in 2020, equivalent to seven per one million people.
The 1,161,100-strong county of Nottinghamshire saw 54 offences in total - 47 per million people - while Cambridgeshire’s stats, with its population of 855,800 had 47 offences, equals 55 per million people.
The most common illegal vehicle modification detected by police is the alteration of a number plate - 13,720 such offences occurred in the UK last year, making up 56 per cent of total illegal vehicle modifications. Illegally altered lights made up 23 per cent, while illegally tinted windows accounted for 17 per cent.
Rank |
Modification |
Total offences |
Percentage of total offences |
1 |
Altered number plates |
13,720 |
56 per cent |
2 |
Altered lights |
5,723 |
23 per cent |
3 |
Illegally tinted windows |
4,183 |
17 per cent |
4 |
Altered exhausts |
776 |
Three per cent |
Dan Hutson, head of motor insurance at Compare the Market, commented: “Modifications tend to fall into two categories - performance or cosmetic - but any modification, no matter how minor, should be reported to your car insurance provider.
“Lawful modifications can increase car insurance premiums, so it’s best to check with your provider before making any changes, and there are some providers who specialise in modified cars. Modifications which are against the law are likely to invalidate any type of car insurance policy, so do your research beforehand.”
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