What is a black box?

A black box is a casual name for a telematics device. Black boxes are required by some insurance companies, especially for younger drivers in order to reduce their premiums. These devices include GPS and force sensors that know when and where you're driving, and can detect any moments of hard acceleration or braking. Your insurer can use this data to monitor the way you drive and, if it thinks you're driving dangerously, it'll put your premium up to reflect the extra risk.

Black boxes sometimes come as proper physical devices that must be installed in your car. However, some policies simply use the same sensors in your phone to gather information about your driving, which saves having to fit extra hardware in your car.

While black boxes are often touted as a way to reduce premiums for younger drivers, they have faced criticism for being inflexible. Some black-box insurance policies punish drivers for driving late at night, which might be unavoidable for some users. Others may punish an instance of hard braking, even if this was an emergency braking manoeuvre to avoid a much worse outcome. Make sure you closely check the policy documents before deciding whether a black box policy is right for you.