The most common thing we notice when a part-worn comes off a car in Glasgow is what is not there. No PART-WORN lettering anywhere on either sidewall, which the law says should have been the first thing the buyer saw.
So here is the straight answer to the question people actually ask: are part-worn tyres legal? Yes, part-worn tyres are legal to sell in the UK. But they are legal only under conditions set by the Motor Vehicle Tyres (Safety) Regulations 1994, and most of the part-worns we see coming off wheels never met them.
This page sets out every one of those conditions, the evidence on how often they are actually followed, what to physically check if you are buying one anyway, and the honest arithmetic against a new budget tyre. One thing to state plainly up front: this is general information about how UK law works in this area, not legal advice, and a solicitor or Trading Standards is the right route for a specific dispute.
The Short Answer: Are Part-Worn Tyres Legal to Sell?
Yes. Part-worn tyres are legal to sell in the UK, but the Motor Vehicle Tyres (Safety) Regulations 1994 require them to be marked PART-WORN in upper case letters at least 4mm high, to keep their ECE approval mark and ratings, and to have at least 2mm of tread across the full breadth.
There is more to the Regulations than that, including a structural defect list and a two-stage inspection requirement, all covered below. Selling a part-worn that fails any of it is a criminal offence, enforced by Trading Standards. Legal to sell, in other words, but only when the seller does the work the law demands.
What the Motor Vehicle Tyres (Safety) Regulations 1994 Actually Require
These are not guidelines. They are conditions of sale, and a tyre that fails any one of them cannot lawfully be sold as a part-worn.
1. The PART-WORN Marking
The words PART-WORN must appear on the tyre in upper case letters at least 4mm high, permanently and legibly applied.
Here is the detail nearly every summary omits. The marking must not be hot-branded on, and must not be cut into the tyre, because both methods damage the casing the marking is supposed to certify. It has to be applied in a way that does no harm.
This is the first thing to look for and the easiest non-compliance to spot. On our jobs, the unmarked part-worn is the rule rather than the exception, and an unmarked tyre was not sold in line with the Regulations, whatever the seller said at the time.
2. The ECE Approval Mark, Speed Rating and Load Index
A part-worn must retain its original ECE approval mark and its speed and load index.
In plain terms: the approval mark shows the tyre was type approved when new, and the ratings state what it can safely carry and how fast it can safely go. A tyre where these markings have worn away or been buffed off cannot lawfully be sold, because nobody can say what it is rated for.
The ratings also have to work for your car. They must be equal to or higher than the figures on the vehicle placard, found in the driver’s door shut, the fuel filler flap or the handbook.
3. The 2mm Minimum Tread at Point of Sale
A part-worn must have at least 2mm of tread across the full breadth of the tread and around the entire outer circumference at the point of sale.
Note “full breadth”. At sale, the 2mm must be present everywhere across the tread, which is stricter in shape than the in-use rule.
Now the distinction no other page draws. 2mm is a supply requirement placed on the seller. It does not change the 1.6mm in-use limit your car is measured against, taken across the central three-quarters of the breadth around the complete circumference. A tyre sold legally at 2mm is 0.4mm of wear from being illegal on your vehicle. That single fact does most of the arithmetic later on this page.
4. The Structural Defect List
A part-worn must be free of all of the following. Cuts longer than 25mm or 10 per cent of the section width, whichever is greater, that reach the ply or cord. Internal or external lumps, bulges or tears caused by separation of the tyre’s structure. Any exposed ply or cord. And any unrepaired penetration damage.
That last item matters most on a used tyre, for one simple reason. You cannot see from the outside whether a previous puncture was repaired properly from the inside or just plugged from the tread, and a bad repair is a failure waiting for a motorway.
5. Inspection Before and After Fitting
The Regulations require two inspections, and the order is the point. The tyre must be inspected before it is fitted to the rim, which is the only opportunity anyone ever gets to see the inside of the casing. It must then be inspected again after fitting and inflating to the highest operating pressure, which is what reveals a bulge or a separation that only shows under load.
Draw the obvious conclusion. A part-worn sold to you already mounted on a wheel has, by definition, not had the first inspection done in front of you.
6. Who Enforces It and What Happens to Sellers
Enforcement is by Trading Standards, and selling non-compliant part-worn tyres is a criminal offence. If you believe you were sold a tyre that fails these requirements, the complaint belongs with Trading Standards, who investigate sellers, not with a tyre fitter.
The requirements against what you can actually verify:
| Requirement | Can a buyer check it? |
| PART-WORN marking, 4mm upper case | Yes, on sight |
| ECE approval mark and ratings | Yes, on the sidewall |
| 2mm across the full breadth | Yes, with a depth gauge |
| No cuts, lumps, bulges, exposed cord | Partly, by eye and hand |
| No unrepaired penetration damage | No, not once mounted |
| Inspected off the rim before fitting | Only if you watched it happen |
How Often Are These Rules Actually Met?
The rules read well. The evidence on compliance does not.
Trading Standards surveys have repeatedly found very high non-compliance rates in the part-worn trade. The strongest single data point is this: in one Lancashire County Council investigation, none of the part-worn tyres tested met the legal requirements. Not a low pass rate. None.
That is one investigation rather than a national statistic, and it deserves to be read that way. But our own jobs keep confirming its shape. The part-worns that come off cars in front of us are frequently unmarked, and an unmarked part-worn was not sold in compliance with the marking requirement, which is the easiest rule of the six to follow.
The honest qualification belongs here too. Compliant sellers do exist, and the difficulty for a buyer is that there is no easy way to tell one from the other on a forecourt. That is the real problem with the part-worn market. Not that everyone breaks the rules, but that you cannot tell who does.
What to Physically Check Before You Buy One
If you are going to buy a part-worn anyway, buy it with your eyes open. Here is the forecourt inspection, in order.
The Marking
Find PART-WORN in upper case letters, at least 4mm high, permanently applied to the sidewall. If it is not there, the tyre is not being sold in line with the Regulations, whatever the seller says, and everything else they tell you should be weighed accordingly.
The Tread, Measured Properly
Do not accept a glance and a thumbnail. Measure across the full breadth, inner shoulder, centre and outer shoulder, at several points around the tyre. The 2mm sale minimum must be present everywhere, not just in the deepest groove. The 20p coin trick is a rough prompt at best, and how to check if your tyres are legally safe covers proper measurement if you want the full method.
The Age, From the DOT Code
Read the last four digits of the DOT code on the sidewall: week and year of manufacture, so 2523 means week 25 of 2023. The Regulations set no age limit for a part-worn tyre, so a compliant tyre can still be an old one, and the DOT code is the only way to know. Rubber degrades with time as well as use, and cracking with age is its visible signature.
The Sidewalls and the Bead
Run a hand slowly around both sidewalls feeling for lumps, bulges and tears. Look for kerbing damage on the outer shoulder and any glint of exposed cord. Then check the bead area, the edge that grips the rim, for damage from careless removal. Bead damage is common on used casings, completely invisible once the tyre is mounted, and one of the reasons a newly fitted tyre keeps losing air.
Repairs You Cannot See
Ask directly whether the tyre has been repaired, and where. A proper repair is an internal patch, visible only before mounting, and only part of the tread area can legitimately be repaired at all. If the seller cannot answer the question, the tyre is answering it for them.
The False Economy: What You Actually Save
Now the arithmetic, using real published figures on one side and honest reasoning on the other, because part-worn prices vary by seller, so compare against a new budget tyre at £40 to £70 for the tyre and £60 to £100 fitted.
| New budget tyre | Part-worn at the legal minimum | |
| Starting tread | Full, typically around 8mm | 2mm at point of sale |
| Legal margin on your car | Millimetres of wear in hand | 0.4mm above the 1.6mm limit |
| History | None, known start point | Unknown |
| Warranty | Manufacturer warranty | Varies by seller |
| Fitted price | £60 to £100, four for £240 to £400 | Whatever the seller asks, plus fitting |
Think in cost per usable millimetre rather than headline price. A new budget tyre arrives with its full tread and a manufacturer warranty. A part-worn sold at the legal minimum arrives 0.4mm from illegal, which on a normal car can be months of driving, not years. At that point it needs replacing again, the fitting has been paid twice, and the saving has quietly gone.
We have seen exactly this cycle: the bargain tyre back at the wear indicators within a season, and the second bill arriving before the first one was forgotten. The cheap option is only cheap if you never have to buy it twice, and longer tyre life starts with what goes on the car in the first place.
The Company Position
Our published position is that a new budget tyre with a known start point is the better buy nearly every time.
Three reasons sit behind that, and they are the same three we give on the phone. Compliance issues, because the buyer cannot verify the sale met the 1994 Regulations. Hidden damage history, because nobody can tell you what the tyre hit or how it was repaired. Unknown prior treatment, because a tyre run under-inflated or overloaded carries damage that does not show on a forecourt.
For most drivers we actually recommend mid-range over budget, because mid-range closes most of the safety gap to premium. Our stock runs from Landsail and Triangle at budget through Falken, Hankook and Yokohama at mid-range to Michelin, Continental and Bridgestone at premium, all new, all with the manufacturer warranty attached, and fitted at your home across Scotland.
Part-Worns, the MOT and the Law on Your Car
The sale rule and the driving rule are different measurements, and it pays to hold both in your head. A part-worn is measured at sale against 2mm across the full breadth. Your car is measured, every day it is on the road, against 1.6mm across the central three-quarters of the breadth around the complete circumference.
Fitting a compliant part-worn is not itself an offence. But the tyre wears from the day it goes on, and a tyre below 1.6mm, cut, bulged or with exposed cord is a major or dangerous defect at MOT and an automatic fail, regardless of whether it was new or part-worn when fitted.
On the roadside consequence, two sentences will do. A defective tyre can bring a fine of up to £2,500 and 3 penalty points per tyre, with the endorsement code CU30. The full picture, including the points question, is in our guide to the fine for driving on a bald tyre, what makes a tyre illegal in the first place is covered in our worn tyre law guide, and the claim side is in can worn tyres void your car insurance claim.
Frequently Asked Questions
Are part-worn tyres legal in the UK?
Yes, legal to sell and to fit, provided the seller meets the Motor Vehicle Tyres (Safety) Regulations 1994: the PART-WORN marking, a retained ECE approval mark and ratings, at least 2mm of tread across the full breadth, no structural defects and a two-stage inspection.
How much tread does a part-worn tyre need at point of sale?
At least 2mm across the full breadth of the tread and around the entire outer circumference. That is a supply rule on the seller. Your car is still measured against the 1.6mm in-use limit, so a tyre sold at 2mm is 0.4mm from illegal.
Do part-worn tyres have to be marked PART-WORN?
Yes. The marking must read PART-WORN in upper case letters at least 4mm high, permanently and legibly applied, and it must not be hot-branded on or cut into the tyre. An unmarked part-worn has not been sold in line with the Regulations.
Are part-worn tyres safe?
A part-worn can meet every requirement of the 1994 Regulations and still carry a history you cannot see: old repairs, kerb strikes, running under-inflated. The Regulations control condition at sale, not the tyre’s past, which is why we recommend a new budget tyre instead.
Can a part-worn tyre pass an MOT?
Yes, if it is above 1.6mm across the central three-quarters and free of defects on test day. The MOT does not care what the tyre cost. It cares about tread and condition, and a part-worn starts far closer to the fail line than a new tyre does.
Are part-worn tyres cheaper than new budget tyres?
Often on headline price, rarely per usable millimetre. A new budget tyre is £40 to £70 alone and £60 to £100 fitted with full tread and a manufacturer warranty. A part-worn near the 2mm minimum may need replacing within months, with fitting paid twice.
Who enforces the part-worn tyre rules?
Trading Standards. Selling non-compliant part-worn tyres is a criminal offence, and a complaint about a specific sale belongs with them. Trading Standards surveys have repeatedly found very high non-compliance rates in the part-worn trade.
What should I check before buying a part-worn tyre?
Five things: the PART-WORN marking, the tread measured across the full breadth at several points, the age from the DOT code, the sidewalls and bead by hand and eye, and the repair history. We check all of this on every tyre before fitting anywhere in Glasgow.
Get a New Tyre Fitted Where You Are
If the arithmetic above has settled it, the next step is one message. Send a photo of the tyre sidewall and your postcode to 07955 533000 on phone or WhatsApp. You get one total on the call before the van moves, nothing added at the roadside, and payment is card at the vehicle, contactless included, after the work.
We are 24/7 Mobile Tyre Services, family run for over 20 years with fully certified technicians, based at 100 Jessie St, Polmadie, Glasgow G42 0PG, working 24 hours a day, 7 days a week in all weather. Average arrival across Glasgow and the Central Belt is 30 to 45 minutes, covering the City Centre, Southside, West End, Partick and Govan plus Paisley, Rutherglen, Bearsden and East Kilbride.
This page is general information about how UK law works in this area rather than legal advice, and a complaint about a specific sale is a matter for Trading Standards.
