When to use fog lights and how to use them

Now that autumn has officially arrived, the leaves are turning vibrant shades of red and gold, Halloween decorations are filling local stores, and the mornings are becoming cold and foggy.
Fog adds a chill to the air and it also reduces visibility, making it challenging to get behind the wheel. Fog can blur objects in the distance and distort lights from other vehicles, making it harder to judge distances and speeds. For this reason, cars come with fog lights, which can help improve visibility and minimise glare. Fog lights are specially designed lamps that emit a low and wide beam of light aimed at the road's surface, which helps you see the road more clearly. There are a few things to keep in mind when using fog lights.

Fog lights should only be used in conditions where visibility is severely reduced, typically to less than 100 metres. Using fog lights when visibility is fine can dazzle other road users. According to the Highway Code Rule 226, you must switch them off when visibility improves.

Your front fog lights help shine a broad, low beam that illuminates the road directly in front of your car. Having increased visibility of the road ahead helps you and other road users stay safe.
Front fog lights are typically either white or yellow coloured.

When to use rear fog lights

Cars are also fitted with rear fog lights, which are extra-bright lights on the back of the vehicle. Rear fog lights are typically red in colour and help make you more visible in thick fog to the drivers behind you.
Rear fog lights are especially bright and should be turned off once visibility improves. If you use rear fog light in good weather conditions, you can blind drivers behind you. Since 1998, it’s been a legal requirement for all new cars to be fitted with rear fog lights.

Different cars have different ways to switch the fog lights on.
There’s usually either a button or a dial on the dashboard, or a switch on the steering wheel stalk. In most cars, there’s an amber indicator for rear fog lights and a green indicator for front fog lights, though this may differ for different cars so you should consult your car’s manual to ensure you’re using the correct settings.

When driving in fog, you should reduce your speed, maintain a safe distance from the car in front of you, and avoid using high beams which can create glare. Fog lights should be used when visibility is severely reduced, but be sure to turn them off when conditions improve.
Read our complete guide on how to drive in adverse weather.

Yes, fog lights are part of the MOT test in the UK for some cars, depending on when the rear and front fog lights were used. According to Gov.uk, the fog lights are inspected on cars that have:
• front fog lamps fitted to vehicles first used on or after 1 March 2018 • the rear fog lamp fitted to the centre or offside of vehicles, first used on or after 1 April 1980 If these cars have fog lights that aren’t functioning properly, have a defective lens or aren’t attached properly, then you may get a minor or a major fault.

Before you head out in your car, make sure you check the weather. If the weather is going to be bad, you may to want to wait or postpone your journey if it's not important.
The Met Office issues adverse weather warnings when thick fog is expected, so you should also keep an eye on their website. According to the Met Office, severe disruption to transport can occur when visibility falls below 50 metres over a wide area, so it's good to be prepared before you drive in the fog.

So if you’re about to hit the road, it can be useful to check the weather forecast so that you can prepare in advance. During winters, it can be especially useful to carry essentials such as hi-vis jackets and a first aid kit in case of emergencies.
Read our guide on how to prepare for winter driving.