The number of UK motorists using telematics-based insurance policies to reduce premiums increased 40% last year, according to the British Insurance Brokers’ Association.

The association surveyed 30 leading telematics brands to determine take-up.

It says there are now almost 455,000 live policies, compared with 323,000 in December 2014.

Such policies can save careful drivers up to 25%.

The policies usually feature “black boxes” in vehicles that monitor factors such as journey times, speed, cornering, acceleration, braking and familiarity of routes. These are analysed to give a risk profile, with the safest drivers enjoying the biggest discounts.

Association Executive Director Graeme Trudgill says telematics policies are becoming the car cover of choice for young drivers, who typically face high premiums.

“Industry statistics show there is a 40% drop in crash risk when a new driver has a telematics policy,” he said. “Telematics equipment also helps reduce theft claims, with many doubling as vehicle tracker devices.”

Mr Trudgill says the benefits of telematics include cheaper premiums, safer roads, less uninsured driving and increased safety, because some systems also operate as breakdown locators.