Are dazzling headlights causing danger on our roads?

Headlight glare causes concern on dark winter nights

The topic of bright headlights dazzling oncoming drivers has become a matter of real concern for many motorists and has even become the subject of independent research commissioned by the UK government.

The RAC has surveyed and written extensively on this subject, with a 2025 RAC survey reporting that most drivers who participated believe either all or some headlights are too bright. This belief is partially backed up in fact, at least in terms of newer cars fitted with LED lights, as the LED lights can typically emit 200 lumens per watt compared to only 24 lumens per watt in halogen lights. This has clear benefits for drivers whose vehicles are fitted with LED lights, improving visibility at night, but the evidence suggests that there may be significant negative effects for oncoming motorists affected by bright lights.

The survey reveals glare caused by bright headlights is blamed by motorists for a range of problems, from short term issues like discomfort or temporary blinding, to lasting effects such as eye pain and migraine. Further, 52% of drivers in the RAC survey have either stopped, reduced or would like to reduce the amount they drive at night due to the brightness of other vehicles’ lights.

Are dazzling headlights actually dangerous?

While the data may be worthy of some scrutiny due to factors such as attending police officers’ expertise in recording causes of a crash, nonetheless the RAC reports that during 2014-2023 an average of 263 collisions per year occur where dazzling lights are a factor. The majority are non-fatal accidents but every year in this period saw several fatal accidents attributed to this cause.

Furthermore, drivers surveyed by the RAC report various effects of glare which seriously reduce the ability to drive safely at night, including difficulties in seeing indicators, judging distance or position and speed of oncoming vehicles.

Why has headlight glare or dazzling lights become an issue?

There appears to be no single cause, but a few reasons have been highlighted in the press and by motoring organisations.

As mentioned above, the brightness of new lighting systems with more focussed and less diffuse beams has been identified as a factor. In addition, the RAC reports that some drivers may be replacing car headlight bulbs with illegal aftermarket LEDS, for which the lights are not designed.

While the beams of such vehicles should technically be angled to avoid glare, vehicles with a high ride height (such as SUVs and 4x4s) receive a portion of blame from drivers surveyed. These vehicles have become more common in recent years, and in RAC data are noticeably blamed by drivers who use vehicles with a lower ride height.

Although an issue not restricted to current times, incorrect headlight alignment is also a potential cause of dazzle. Headlights should firstly be set with in-vehicle controls to take account of the load of the vehicle, which affects the angle of the beam. Secondly, misaligned headlights are a common cause of MOT failure, and it’s stated in the Highway Code that vehicles must not dazzle other drivers. All of which emphasises that there is good reason to keep headlights clean, well maintained and in good working order, as well as taking basic care not to dazzle other drivers.

Therefore, as always, if one is ever at all in doubt about maintenance of your vehicle’s headlights, a reliable course of action is to consult a reputable local garage, such as our workshop here at Dowleys.