Drivers have been warned they could see their insurance costs surge by as much as 16 per cent if they make modifications to their vehicles.

A recent study examined how various alterations affect premiums across 10 major UK cities, with drivers facing higher costs.

Performance-enhancing changes proved the costliest for drivers' wallets, with modifications resulting in steep premium charges.

The research compared insurance quotations using identical driver profiles and vehicle specifications, with only the type of modification varying between quotes.

GETTY |

Experts have warned drivers not to make changes to their vehicles which could see insurance spike

Even seemingly minor alterations showed significant impacts on insurance costs, suggesting drivers should carefully consider the financial implications before upgrading their vehicles.

The analysis identified four modifications that trigger the steepest premium increases with suspension alterations, complete body kit installations, exhaust system changes and engine chipping or remapping, each pushing insurance costs up by 15.93 per cent on average.

These performance-focused upgrades signal to insurance providers that vehicle owners might engage in riskier driving behaviours.

The identical premium increases across these four modification categories suggest insurers view them as equally significant risk factors.

GETTY |

Car insurance prices can increase if drivers modify their vehicles

Beyond performance enhancements, aesthetic changes also carry substantial costs, with rear spoilers and window tinting both resulting in 12.10 per cent premium increases.

Safety improvements like upgraded braking systems added 4.52 per cent to insurance costs, matching the increase for cosmetic alterations such as custom paint jobs and side skirt installations.

Geographic factors also played a crucial role in determining modification-related insurance increases, experts explained.

The capital faces the steepest rises, with London motorists experiencing average premium increases of 8.88 per cent when modifying their vehicles.

Liverpool residents encounter nearly identical challenges, with modifications adding 8.72 per cent to their insurance costs.

Leeds rounded out the top three most expensive locations at 8.53 per cent.

Belfast and Bristol emerged as the most affordable locations for modified vehicle insurance, with average increases of just 7.01 per cent and seven per cent respectively.

Insurance providers consider multiple location-specific factors when calculating premiums, including historical crime statistics and traffic incident data.

These regional variations mean identical modifications can result in vastly different insurance costs depending on postcode.

GETTY

Sam Sheehan, motoring editor at cinch, said. "You don't want to be surprised by an increase of a couple of hundred pounds for what feels like a small modification.

"Something as simple as tinted windows can add over 12 per cent to your annual premium, and a safety upgrade can make your insurance go up too."

The expert recommended that motorists factor insurance implications into their modification budgets from the outset.

"What seems like a harmless upgrade could result in a costly surprise when renewal time comes around," Sheehan warned.

The research uncovered surprising variations in how different modifications affect premiums.

Window tinting and rear spoilers both increase insurance costs by 12.10 per cent, despite being purely cosmetic changes.