MOT advisory explained
“Tyre worn on the inner edge”
This is the only line on your certificate that is a diagnosis rather than a condition. The tyre is not the fault — it is the paper the fault has been writing on, and buying a new one without reading it means buying another next year.
One shoulder of the tread has worn faster than the rest. The tyre still has legal depth where the test measures it, which is why this is an advisory — but a tyre wearing on one edge is being held at an angle it was not designed to sit at.
Deal with the cause before the tyre. A new tyre fitted to a car with the same geometry wears the same way, on the same edge, in the same number of miles.
One tyre at £60–£120 plus an alignment at £40–£80. If a worn suspension component caused it, that is a separate job on top — suspension repair costs by model.
A tyre fitted without checking why the old one wore that way is the most common avoidable repeat bill on a car. The alignment costs less than the second tyre.
A “tyre worn on the inner edge” advisory means one shoulder of the tread has worn faster than the rest — a symptom of alignment or suspension — but it is still legal, so the car passes. Correcting it costs £100–£200: one tyre plus an alignment. Of 46 million tracked tyre advisories, 9.9% later returned as a failure.
How this reads on your certificate
Inner or outer, nearside or offside. “Nearside front tyre worn on inner edge”, “offside rear tyre worn close to the legal limit on the outer shoulder”. Nearside is the passenger side of the car, offside the driver’s side. Inner means the edge nearest the middle of the car — the one you cannot see standing beside it.
Inner and outer point in different directions. Inner-edge wear is by far the more common and usually means the top of the wheel leans inward, or the wheels are pointing very slightly outward from each other. Outer-edge wear is the reverse, and on a family car it more often follows a kerb strike or a lowered ride height than a gradual drift.
Both edges worn is a different fault entirely. That is under-inflation, not geometry — the tyre bulges and rides on its shoulders. It is free to fix and worth checking before anyone books an alignment.
The corner matters as much as the wording. One tyre worn on the inner edge is a corner problem. Both fronts worn on their inner edges is usually a tracking problem across the axle. Both rears, on many modern cars with independent rear suspension, is a camber setting that has drifted or a tired bush at the back.
What actually causes it
Four things produce this wear pattern, and they cost very different amounts to put right. The first two are adjustments. The second two are repairs.
- Camber — the wheel leaning. Viewed from the front, the top of the wheel tilts inward. Some negative camber is designed in on most cars for cornering stability, and a small amount of inner wear is therefore normal over a tyre’s life. Too much, and the inner shoulder carries load the rest of the tread never sees.
- Toe — the wheels not pointing straight. The most common cause and the cheapest to fix. Wheels toed even slightly out are dragged sideways a fraction of an inch for every foot the car travels, and that scrubbing lands on one shoulder. A pothole or a firm kerb strike is usually enough to knock it out.
- A worn suspension component. A perished arm bush or a loose ball joint lets the wheel move under load, so the geometry is correct when the car is standing still on the alignment rig and wrong every time you brake or corner. This is the case where an alignment alone will not hold — the numbers are set correctly and drift straight back out.
- Ride height that has changed. Suspension geometry is designed around a particular height. Tired springs settle, and lowering springs move it deliberately. Either way the camber goes with it, which is why lowered cars are known for eating inner shoulders.
Which is why the honest sequence is diagnosis, then repair, then alignment, then tyre. Aligning a car with a worn joint sets numbers that will not stay. Fitting a tyre before the alignment starts the clock on the new one straight away.
The check that misses this one
On a tyre worn close to the limit, the useful advice is that you can check it yourself with a 20p coin and need nobody’s opinion. That is true, and this advisory is the exception that proves how it goes wrong.
The inner shoulder is the one part of the tyre you never see. Standing beside the car you are looking at the outer face. The edge doing the wearing is on the far side, tucked behind the wheel arch, and it can be almost gone while everything visible looks perfectly healthy.
Two ways round it, both free. Turn the steering onto full lock and the front tyre swings out where you can see its inner face directly — this is the single most useful thirty seconds you can spend on a car’s tyres. For the rears, run a flat hand across the tread from outer to inner; a shoulder that has worn down feels like a step rather than a curve, and hands find that far better than eyes do.
Feel for feathering while you are there. Run your palm across the tread in both directions. If it feels smooth one way and like the teeth of a saw the other, the tread blocks have worn at an angle — which is toe wear, caught early, before the shoulder itself has gone.
Two different rules on the same tyre
This advisory sits exactly where the MOT’s tyre rules disagree with each other, and understanding that is worth more than any argument about how much tread is left.
Tread depth is measured across the central three-quarters of the tread. The outer eighth on each side does not count. So a tyre can have a badly worn inner shoulder and still pass on depth, because the shoulder sits outside the band where the 1.6 mm minimum applies. That is the rule that made this an advisory rather than a failure today.
Exposed cord or ply fails anywhere on the tyre. No band, no three-quarters, no measurement. Once the structure of the tyre is showing, it is a major defect wherever it appears — including on the shoulder the depth rule ignores.
So this fault crosses from advisory to failure without passing through the depth rule at all. The inner shoulder keeps wearing in a place the measurement does not reach, and the day it reaches cord it is an instant failure. There is no gradual warning in the numbers, because the numbers were never watching that part of the tyre.
The practical version: do not reason about this one from tread depth. Ask what the inner shoulder looks like, and if the answer involves the word “nearly”, act on it.
How often does this advisory become a failure?
This can be measured rather than guessed. Following every tyre advisory forward to the same vehicle’s later tests, across 46 million of them — the largest single category in the record — shows what actually happened.
| What happened next | Tyres | Suspension | Brake parts |
|---|---|---|---|
| Became a failure at a later test | 9.9% | 18.7% | 9.4% |
| Ignored, no action taken | 30.5% | 37.1% | 36.1% |
| Fixed | 59.6% | 44.2% | 54.4% |
| Median advisory to failure | 376–379 days — the next MOT | ||
From the DVSA MOT testing bulk dataset (Open Government Licence v3.0): 829.7 million tests and 145.1 million advisories tracked to each vehicle’s later tests, from 46,001,206 tyre advisories. Tyres account for 23.8% of all recorded MOT defects, more than any other component group.
Tyres have the highest fix rate of anything measured — 59.6%. On most advisories that would be the end of the story. Here it is worth one more question, because of what the word “fixed” is actually counting.
The record shows whether the tyre was sound at the following test. It cannot show whether the reason it wore that way was ever addressed. Those are different events, and for edge wear they come apart completely: a new tyre makes the advisory disappear whether or not the geometry was touched.
So a car can appear in the 59.6% three years running — three tyres, three clean certificates — while the fault that ate all three was never found. The tyre is the only part of this the test can see, and the tyre is the symptom.
Which makes the alignment printout the document that matters here, not the MOT certificate. One shows what was corrected; the other only shows what was replaced.
What it costs
| Job | Price fitted | Notes |
|---|---|---|
| Wheel alignment | £40–£80 | Ask for the before and after printout |
| One tyre, common size | £60–£120 | Includes balancing, valve and disposal |
| Worn bush or ball joint, if that is the cause | £70–£280 | Ball joint at the low end, complete arm at the top |
| Four-wheel alignment | Higher | Needed where the rear is adjustable too |
Independent garage and tyre-fitter prices. Main dealers typically charge around 50% more. Component prices from the suspension repair cost page, which has the figure for your model.
The printout is the part you are paying for. An alignment without before-and-after figures is a receipt, not a repair. Ask for the sheet showing camber and toe on each corner against the manufacturer’s tolerance, and keep it — it is also the document that tells you whether the next tyre wearing unevenly is a new fault or the same one.
Front-only tracking is not always enough. Many modern cars have adjustable rear geometry, and a rear tyre wearing on its inner edge cannot be corrected by setting the front. If the advisory names a rear tyre, a two-wheel alignment will not touch it.
Check the other side before agreeing to a pair. Geometry faults are often one-sided, especially after a kerb strike, and the matching tyre may have plenty of life left. Replacing in pairs is sound advice when both are worn evenly and equally — it is not automatic when one corner has a fault the other does not.
If a suspension component is the cause, sequence saves money. Repair first, align second, tyre last. Reverse that order and you pay for the alignment twice, or for the tyre twice, depending on which step you skipped.
| Worked example — one front tyre plus geometry, family hatchback | |
|---|---|
| Mid-range tyre, 16-inch | £68 |
| Fitting, balancing, valve and disposal | £15 |
| Four-wheel alignment with printout | £60 |
| Typical total | ≈ £143 |
Sits in the middle of the £100–£200 range. This assumes nothing is worn — if a bush or ball joint turns out to be the cause, add that repair and the alignment comes after it rather than before.
Enter your reg — we’ll read your MOT history, decode each advisory and price it for your exact model.
What to do next
- Look at the inner edge yourself, on full lock. Thirty seconds, no tools, and it tells you whether you are looking at early feathering or a shoulder that is nearly gone. Those two answers have different timescales.
- Check the pressures first. If both edges are worn rather than one, this is under-inflation and not geometry at all — free to fix, and no alignment needed.
- Ask whether anything is worn before booking the alignment. If a bush or joint is letting the wheel move, the alignment will not hold and you will pay for it twice. This is the question that decides the order of the work.
- Insist on the before-and-after printout. It is the only proof the geometry was actually corrected rather than just measured, and it is the reference point if the next tyre starts wearing the same way.
Inner edge tyre wear FAQ
What causes a tyre to wear on the inner edge?
Geometry rather than the tyre. The usual causes are excessive negative camber, wheels toed slightly outward, a worn suspension bush or ball joint letting the wheel move under load, or a ride height that has changed through tired or lowered springs. All four hold the tyre at an angle it was not designed to run at.
Will wheel alignment fix inner edge wear?
It fixes the cause when the cause is an adjustment. It does not when something is worn: a perished bush or a loose ball joint lets the wheel move under load, so the numbers are correct on the rig and wrong on the road, and they drift back out within weeks. Ask whether anything is worn before booking the alignment.
Can a tyre worn on the inner edge still pass an MOT?
Yes, and often does. Tread depth is measured across the central three-quarters of the tread, so a worn shoulder sits outside the band where the 1.6 mm minimum applies. But exposed cord or ply is a major defect anywhere on the tyre, including that shoulder — so this fault can go from advisory to failure without the depth measurement ever changing.
How do I check the inner edge of my tyre?
Turn the steering onto full lock and the front tyre swings out where you can see its inner face directly. For the rears, run a flat hand across the tread from the outer to the inner side — a worn shoulder feels like a step rather than a curve, and hands detect that far better than eyes.
Is inner edge wear dangerous?
Not immediately, at the advisory stage. The concern is that the wear is happening where the MOT measurement does not look, so it can reach exposed cord without any warning from tread depth. A tyre with structure showing can deflate suddenly, which is why “nearly through” is worth acting on rather than monitoring.
Should I replace the tyre before or after the alignment?
After. A new tyre fitted to a car with the same geometry starts wearing the same way immediately, so aligning first means the new tyre gets a full life rather than a repeat of the old one’s. If a worn component caused the problem, repair that first, then align, then fit the tyre.
Why is only one of my tyres wearing on the inner edge?
Geometry faults are frequently one-sided, most often after a kerb strike or a pothole hit on that corner. It is also what you would expect from a worn bush or joint on that side alone. Because of this, replacing in pairs is not automatic here — check what the other tyre actually measures before agreeing to two.
Does an inner edge tyre advisory usually become an MOT failure?
Across 46 million tracked tyre advisories, 9.9% returned as a failure at a later test and 59.6% were recorded as fixed. Read the fix rate carefully for edge wear, though: it counts tyres that were sound at the next test, not causes that were corrected. A car can appear as fixed several years running while the geometry fault that wore each tyre was never addressed.