What Is the Legal Tyre Tread Depth in the UK?

How low can tyre tread go before it is illegal?

The line is 1.6mm. Below that, a car tyre is illegal on UK roads and fails the MOT.

The rule is not “1.6mm somewhere”. It covers the central three-quarters of the tread width, all the way round. A tyre that looks fine on the inner shoulder but is worn through in the middle is still illegal.

When you check by eye, look across the tyre and around it, not at one spot.

Is 2mm tyre tread legal, and is 3mm tread OK for the MOT?

Yes to both. A tyre with 2mm or 3mm of tread is above the 1.6mm legal minimum, so it is legal and it passes the MOT tread test. Neither is the same as “good”: 3mm is the point TyreSafe says to start considering replacement.

A tyre at 2mm is close to the limit. One more wet winter can take it under.

Is 1.6mm actually safe, or just legal?

Legal and safe are different things. 1.6mm is where the law says stop. It is not where a tyre grips well.

Shallow grooves clear less water, so a tyre with 2mm in a downpour has less to work with than one with 5mm. TyreSafe advises considering replacement below 3mm for that reason.

Think of 1.6mm as the cliff edge and 3mm as the fence. Replace at the fence if you drive through Manchester’s wet months.

How do I check my tread depth at home?

Use a tread depth gauge or the 20p test TyreSafe publishes. Both take a minute.

1. Pick a groove in the central part of the tyre.
2. Measure it, or place the coin in the groove as TyreSafe’s guide shows.
3. Repeat at three points around the tyre.
4. Repeat on all four tyres, and on the spare if you use it.

Also look for cuts, bulges and cracking on the sidewalls. A tyre can be legal on tread and still unsafe.

Does the 20p test work?

Yes, as a screening check. If the outer band of a 20p coin is hidden when placed in a groove, the tread is above the legal limit. If the band is visible, the tyre may be illegal and a tyre professional should check it at once. Source: www.tyresafe.org/the-checks/tread-depth/20p-test/

The coin gives a pass or a warning, not a number. A gauge gives the number.

What will the MOT fail on?

The MOT looks at more than tread. Testers inspect tyres for condition, security, size and type as well as depth.

Tread below 1.6mm is a fail. So is any exposed ply or cord, and so is a lump or bulge from structural failure, which the MOT manual treats as a dangerous defect. Source: www.gov.uk/government/publications/car-parts-checked-at-an-m

Cars first used on or after 1 January 2012 also have the tyre pressure monitoring warning light checked. If your MOT is coming up, check tread first. It is the cheapest fail to avoid.

How much is the fine for a bald tyre?

GOV.UK states a fine of up to £2,500 and 3 penalty points per illegal tyre. “Per tyre” means four bald tyres can multiply the penalty.

Insurance is a separate worry. Check your policy wording or ask your insurer how it treats tyre condition.

Legal versus safe: the contrast that matters

Winter widens the gap. TyreSafe says tread should be “well above” the legal minimum through the colder months.

What does tread depth mean for drivers in Gorton and east Manchester?

Local driving is short, stop-start and often wet. Tyres on short urban trips wear differently from motorway miles, and potholes add impact damage that tread depth alone will not show.

Hyde Road Wheels & Tyres in Gorton, M12 5FH, is rated 4.4 on Google from more than 770 reviews, and tyre replacement is the job customers mention most in those reviews. If a tyre is close to the line, see the new tyres we fit in Manchester or ring ahead on 0161 274 3125. We are open Monday to Friday 9:00 to 17:30 and Saturday 9:00 to 16:30, and closed on Sunday.

What comes after legal tread: the rule for used tyres

Used tyres sold in the UK need a higher 2mm minimum at the point of sale: see are part-worn tyres legal. For cold-weather grip beyond tread depth, read winter tyres or all-season in Manchester.