can you use fog lights within 100m of another car

[OArya]

No, you should not use your fog lights when you are within 100 meters (about 328 feet) of another car traveling in the same direction. Fog lights are designed for low-visibility conditions, not for regular driving near other vehicles. Using them incorrectly can create a dangerous glare for other drivers, reducing their ability to see the road clearly.

The primary purpose of fog lights is to cut under the fog, mist, or heavy rain, illuminating the road surface close to your vehicle without reflecting light back into your eyes. Their beam pattern is wide and flat, unlike the focused, longer-range beam of regular headlights. When you are following another car or when one is approaching you, this bright, low-spreading light can be blinding through their rearview or side mirrors.

Many state laws specifically regulate fog light use. They are typically permitted only when visibility is significantly reduced, and most laws require you to turn them off when within a certain distance of another vehicle to prevent glare. It's a matter of both safety and courtesy.

State	Fog Light Color Restriction	Required Distance from Other Vehicles	Legal Use Limited to Low Visibility?
California	Amber or White	Not specified, but glare prohibited	Yes
Texas	Amber or White	Must be turned off within 500 ft	Yes
New York	Amber or White	Not explicitly defined	Yes
Florida	White	Must not project glaring light	Yes
Illinois	Amber or White	Use must not blind others	Yes

The best practice is to treat your high beams and fog lights with similar caution. If you wouldn't use your high beams because of an oncoming car or one you're following, you should turn off your fog lights as well. Only activate them when you genuinely need the extra light close to your car due to weather, and deactivate them as soon as conditions improve or traffic appears.

[Dante]

Think of it like high beams. If you're close enough to another car that you'd dim your brights, you should turn off the fog lights too. That light bounces off their mirrors and makes it hard for them to see. It's just polite driving. Save them for when you're alone on a foggy road and really need that extra light down low.

[LaTravis]

From a safety standpoint, it's a significant risk. The intense, low-aimed beam of fog lights creates a pool of bright light that reflects directly into the mirrors of the car in front of you. This glare compromises the lead driver's vision, especially at night, and can cause them to miss hazards on the road. It's not just annoying; it's actively hazardous. Always err on the side of caution and switch them off when closing in on another vehicle.

[Megan]

Where I live, the law is pretty clear: if you're using fog lights, you have to turn them off when you get within 500 feet of a car. A cop can pull you over for that alone. It's considered an unnecessary and distracting light. I only ever flip mine on during a real pea-soup fog, and the second I see taillights up ahead, they're off. It's not worth the ticket or causing an accident.

[AnaMarie]

Technically, fog lights are a tool for specific conditions. Their value is lost when you're near other traffic. The light scatter can be worse than regular headlights because it's aimed low and wide. If it's not foggy, you're just adding glare with no benefit. If it is foggy and you're tailing someone, your low beams are sufficient. The car ahead is already breaking a path. Using fog lights in that situation is overkill and impolite. The rule is simple: use them when you're alone and visibility is poor.