When to use fog lights Motorists are often unsure when exactly fog lights should and shouldn't be used. Although it is a legal requirement to have fog lights fitted, there is no legal obligation to actually use them, even when it's foggy. Using them in foggy conditions will of course increase safety. If your vehicle has rear fog lights only, it will increase your visibility for other motorists when turned on.

Fog lights

Turn on fog lights when visibility is reduced to around 100 metres and less. It can be a little difficult to judge 100 metres, so think along the lines of the length of a football pitch.

Turn off fog lights

Remember however to turn off your fog lights if the fog clears. Keeping fog lights on when visibility is clear is hazardous for other motorists. Drivers following behind will be dazzled by the very bright rear fog light(s), particularly at night. It is illegal to drive with fog light on in clear weather conditions.

If stopped by the police, you may be lucky enough to be let off with a verbal warning, ultimately however, you may be issued with a non-endorsable (no penalty points) Fixed Penalty Notice (FPN) which comes with a fine of £30.