DVLA eyesight standards & cataracts: the UK rules for driving

The DVLA Group 1 (car and motorcycle) eyesight standard has three parts: you must be able to read a current-style number plate from 20 metres (about 5 car lengths) in good daylight, have a visual acuity of at least 6/12 (decimal 0.5) measured with both eyes open — or in the better eye if you only have sight in one eye — and have an adequate field of vision. Cataracts can blur acuity and dazzle you with glare long before you fail the plate test, so it is worth checking your sight early. After cataract surgery, most people meet the standard within days and can return to driving once their vision is comfortably clear and stable.

The DVLA eyesight standard for driving

Everyone who drives in Great Britain must meet a minimum eyesight standard at all times — not just when they take their test. For ordinary car and motorcycle drivers (Group 1 licences) the standard has three components, and you must meet all of them.

1. The number-plate test (20 metres)

You must be able to read, in good daylight, the registration mark on a vehicle fitted with a current-style number plate from a distance of 20 metres. That is roughly five car lengths, or about 8 parking-bay widths. You may wear glasses or contact lenses to do this — but if you do, you must wear them every time you drive. This is the practical, everyday test the police can ask you to perform at the roadside.

2. Visual acuity (6/12)

Your visual acuity must be at least 6/12 on the Snellen scale (a decimal acuity of 0.5), measured with both eyes open — or, if you have sight in one eye only, in that eye. Again, glasses or contact lenses are allowed to reach this level. 6/12 means you can see at 6 metres what a person with standard vision sees at 12 metres; it is roughly half of normal 6/6 (20/20) vision.

3. An adequate field of vision

You must have an adequate horizontal and vertical field of vision — your peripheral awareness of what is around you, not just straight ahead. Conditions such as glaucoma, stroke or advanced diabetic eye disease can shrink the visual field even when central acuity is good. Cataracts on their own do not usually narrow the field, but they frequently reduce acuity and cause disabling glare.

Driving with cataracts

A cataract is the gradual clouding of the eye's natural lens. Because it develops slowly, many people do not realise how much their driving vision has deteriorated. The earliest warning signs tend to show up behind the wheel:

• Glare and dazzle from oncoming headlights at night, with starbursts or halos around bright lights.
• Difficulty reading road signs or number plates that used to be clear.
• Faded or yellowed colours, making traffic lights and brake lights harder to judge.
• Hazy, misted vision in low sun, fog or at dusk.
• Frequent changes to your glasses prescription that no longer fully fix the problem.

Having a cataract does not automatically make you unfit to drive. The legal question is simple: can you still meet the eyesight standard? If you can read a number plate at 20 metres and your acuity is 6/12 or better (with glasses if you wear them), you may continue to drive. If you cannot, you must stop driving until your vision is corrected — and in most cases that means cataract surgery. If you are unsure, ask your optometrist to check your acuity and visual field, and have any cataract assessed by an ophthalmologist.

For a deeper look at the symptoms, lens options and treatment itself, see our full guide to cataract surgery, and why vision can sometimes turn cloudy again years after surgery (a treatable condition called PCO).

When you must tell the DVLA about cataracts

You do not have to tell the DVLA simply because you have been diagnosed with a cataract, provided you still meet the eyesight standard and your optometrist or surgeon has not advised you to stop driving. Most early cataracts fall into this category.

You must tell the DVLA if any of the following apply:

• You cannot meet the eyesight standard — for example you can no longer read a number plate at 20 metres, even with up-to-date glasses.
• Your cataract (or any eye condition) affects both eyes and a doctor has told you it may not be correctable to the required standard.
• You have a reduced visual field, double vision, or another condition your clinician says is notifiable.
• A health professional has advised you not to drive.

It is a criminal offence to drive when you do not meet the standard, and you can be fined up to £1,000 — and you must not drive if you have been told you fail it. If you are in doubt, the safe course is to stop driving and get your eyes checked promptly. Notifiable conditions are reported to the DVLA directly (online or by post); your optometrist or eye clinic can advise you on whether your situation needs to be declared.

Getting cleared to drive again after cataract surgery

Cataract surgery replaces the clouded lens with a clear intraocular lens (IOL), and for most people it restores vision well past the legal driving standard. There is no fixed legal waiting period set by the DVLA for returning to driving after routine cataract surgery — the rule is that you must meet the eyesight standard and feel that your vision is comfortable and stable.

In practice, this is how returning to driving usually works:

1. Day of surgery: do not drive. Your vision is hazy, your eye may be shielded, and you will need someone to take you home.
2. The first day or two: vision clears rapidly. Many people can already read a number plate at 20 metres, but it can still be variable.
3. Your surgeon's advice: at your first post-operative check (often around one week) your surgeon will confirm your acuity and tell you when it is safe to resume driving. Always follow their specific guidance.
4. Second eye: if you are having both eyes treated, your vision may feel unbalanced between operations. Wait until your care team confirms you meet the standard comfortably.

A simple self-check is the 20-metre number-plate test in good daylight: if you can read it clearly and comfortably, and your surgeon is satisfied, you have met the standard. For the full day-by-day picture, read our dedicated guides on when you can drive again after cataract surgery and the week-by-week recovery timeline. Many patients also ask whether they will still need glasses afterwards, which depends on the lens chosen.

Frequently asked questions