Last updated: 31 October 2026
Book your HGV / D4 medical with Dr Steve Walton, Sheffield S12: £80, 30-minute GP examination
1. The number plate test (20 metres)
In good daylight you must be able to read a car number plate:
- from 20 metres for plates in the current font (cars registered since 1 September 2001), which is about the length of 5 parked cars
- from 20.5 metres for older-style plates (before 1 September 2001)
This test is done at the start of every practical driving test. If you can't read the plate, you fail, the test doesn't continue, the DVLA is told and your licence is revoked. To get it back, you'll need to pass an eyesight test with DVSA at a test centre.
Try it yourself
Pace out about 20 metres (roughly 25 adult steps, or 5 car lengths) from a parked car in daylight, wearing your driving glasses if you use them. If you struggle, don't drive and book an eye test.
2. Visual acuity: 6/12
You must also have visual acuity of at least decimal 0.5 (6/12) on the Snellen scale, using both eyes together (or your one eye if you only have sight in one). You can wear glasses or contacts. An optician measures this.
3. Field of vision
The legal minimum for car drivers is a field of at least 120° horizontally, extending at least 50° left and right, with no significant defect within 20° of the centre above or below the horizontal. Conditions such as glaucoma, retinitis pigmentosa, diabetic retinopathy and stroke can reduce your field without you noticing. If the DVLA needs a field test, it uses a binocular Esterman test.
Do I have to tell the DVLA about my eyesight?
GOV.UK says you must tell the DVLA if you have any eyesight problem that affects both eyes, or your remaining eye if you only have one. You don't need to tell them about:
- short or long sight
- colour blindness
- laser surgery for short sight, if you now meet the standard
Examples that may need reporting include glaucoma in both eyes, diabetic retinopathy treated with laser, macular degeneration, double vision and visual field loss after a stroke. Cataracts often don't need reporting if you still meet the standard, but glare can stop you passing the number plate test even when the chart reading looks fine.
Sight in one eye
Car drivers who have lost the sight of one eye can drive once they've adapted, if they meet the same acuity and field standards as other drivers. Only those who can't meet the standards need to notify the DVLA. Lorry and bus licensing is normally barred.
Double vision
You must stop driving and tell the DVLA. You can drive again once it is controlled, for example with glasses or a patch you undertake to wear while driving.
What if I report an eye condition?
The DVLA may send you for an eyesight test with its contracted optician, which is free. You can use your own optician instead if the test includes an Esterman visual field test, but you'll pay, and the DVLA doesn't guarantee to accept it. Driving without meeting the standards can lead to prosecution.
Older drivers and eyesight
When you renew your licence at 70, and every 3 years after, you declare that you meet the eyesight standard. Nobody tests you at renewal, so it's up to you to make sure. Common age-related problems such as cataract, glaucoma and macular degeneration develop gradually, and many people don't notice their vision has dropped. Regular eye tests pick these up early, and many causes, especially cataracts, are very treatable.
Practical tips
- Have an eye test at least every 2 years, or as your optician advises.
- Keep a spare pair of glasses in the car.
- Night glare getting worse? Ask about cataracts.
Thinking of a lorry, bus or minibus licence?
The Group 2 standard is much higher: 6/7.5 in the better eye, 6/60 in the other, a +8 dioptre limit on glasses and a 160° field. See our HGV eyesight standards and download the D4 form.
Book your HGV / D4 medical with Dr Steve Walton, Sheffield S12: £80, 30-minute GP examination
Frequently asked questions
How far away do you need to read a number plate to drive?
20 metres for a modern number plate (cars registered since 1 September 2001), or 20.5 metres for older-style plates, in good daylight with glasses or contacts if needed.
What is the minimum eyesight for driving a car?
Visual acuity of at least 6/12 (decimal 0.5) with both eyes together, the 20-metre number plate test, and an adequate field of vision of at least 120° horizontally.
Do I need to tell the DVLA if I wear glasses?
No. Short or long sight doesn't need reporting, but you must wear your glasses or lenses every time you drive if you need them to meet the standard.
Do I need to tell the DVLA about glaucoma?
You must tell DVLA about any eye condition affecting both eyes, or your remaining eye if you only have one. That includes glaucoma in both eyes.
What happens if I fail the number plate test on my driving test?
The test stops, you fail, DVLA is told and your licence is revoked. You'll need to pass a DVSA eyesight test when you reapply.
Sources (GOV.UK / DVLA)
Medical standards checked against DVLA's Assessing fitness to drive (November 2025 edition) and GOV.UK guidance, October 2026. Always check GOV.UK for the latest rules.