UK roads have a pothole problem. Local authorities filled over 1.7 million potholes in 2022–23, and the backlog of repairs runs into the billions. For drivers, this means the question isn't whether you'll hit a pothole — it's what happens to your car when you do.
The answer depends on the pothole's depth, your speed, and which part of the wheel takes the impact. A shallow pothole at low speed may cause nothing more than a jolt. A deep pothole at 40 mph can damage the tyre, crack the alloy wheel, knock the alignment out of specification, and stress the suspension — all in the same impact.
What Happens to Your Wheel in a Pothole Impact
When a tyre drops into a pothole and hits the far edge, the impact force is transmitted upward through the tyre sidewall and into the wheel and suspension. The tyre sidewall compresses against the rim, which is why pothole impacts cause pinch punctures — the inner tube or tyre liner is pinched between the rim and the road surface.
At the same time, the impact force pushes the wheel backward and inward, applying a sudden load to the suspension geometry. Suspension components are designed to handle vertical loads — the up-and-down motion of normal driving. A sharp horizontal impact from a pothole applies force in a direction the suspension wasn't designed to absorb, which is why alignment angles can shift even when no components are visibly damaged.
Which Alignment Angles Are Most Affected
Toe is the most commonly affected angle after a pothole impact. The toe angle — whether the front of the tyre points slightly inward or outward — is controlled by the track rod ends, which are relatively lightweight components connected to the steering rack. A hard impact can shift the toe angle on the affected wheel while the other three wheels remain within specification.
Caster is the second most commonly affected angle. Caster is controlled by the position of the upper and lower suspension mounting points, and a severe impact can shift these positions slightly — particularly on MacPherson strut suspensions where the top mount is a single point. Unequal caster between left and right causes the car to pull toward the side with the lower caster value.
Camber is less commonly affected by a single pothole impact unless a suspension component is bent or a mounting point is damaged. If the camber is out after a pothole, there's usually visible damage to inspect.
The Silent Damage Problem
Alignment damage from a pothole often produces no immediate, obvious symptom. The car may not pull noticeably, and the steering may feel normal. But one tyre is now wearing faster than the others — and this continues silently until the wear becomes visible or a routine alignment check reveals the problem. By that point, tyre life has already been lost.
What to Check After Hitting a Pothole
Immediately After the Impact
Pull over safely when possible and walk around the car. Look for a tyre that appears lower than the others — a pinch puncture may not deflate the tyre immediately, but the tyre may be losing air slowly. Check for visible damage to the tyre sidewall: a bulge or cut on the sidewall means the tyre needs replacing, not repairing.
Check the alloy wheel for cracks along the inner rim flange — this is where pothole impacts concentrate. A cracked alloy is a safety issue and cannot be repaired; it needs replacing.
In the Days After the Impact
Monitor whether the car pulls to one side when you release the steering wheel on a straight, level road. Check whether the steering wheel is centred when driving straight — if it's offset to one side, the alignment has shifted. Watch for any vibration that wasn't present before the impact.
If any of these symptoms appear, book an alignment check. Don't wait until the next service — every mile driven with misalignment is wearing your tyre unevenly.
Pothole Damage Checklist
| What to Check | What to Look For | Action If Found |
|---|---|---|
| Tyre pressure | Lower than usual on affected wheel | Inflate and monitor — may be slow puncture |
| Tyre sidewall | Bulge, cut, or visible deformation | Replace tyre — sidewall damage is not repairable |
| Alloy wheel rim | Crack or deep gouge on inner flange | Replace wheel — cracked alloys are unsafe |
| Steering pull | Car drifts left or right on straight road | Book alignment check |
| Steering wheel position | Offset to one side when driving straight | Book alignment check |
| Vibration | New vibration at speed not present before | Book wheel balance and alignment check |
| Ride height | One corner appears lower than others | Book suspension inspection |
When No Symptoms Are Present
The absence of obvious symptoms after a pothole impact doesn't mean the alignment is undamaged. Alignment shifts of 0.2–0.5 degrees — enough to cause measurable tyre wear — often produce no noticeable pull or steering offset. The only way to know whether the alignment is within specification is to measure it on an alignment machine.
If you've hit a significant pothole, booking an alignment check is worthwhile even if the car feels normal. The cost of the check is a fraction of the cost of replacing a tyre that has worn unevenly because of undetected misalignment.
Making a Pothole Damage Claim
Local authorities are legally responsible for maintaining roads in a reasonable condition. If a pothole causes damage to your vehicle, you may be able to claim compensation from the relevant council. To support a claim, you'll need: the exact location and date of the incident, photographs of the pothole and the damage to your vehicle, a repair invoice from a garage, and evidence that the pothole had been reported previously (this is often the deciding factor in whether a claim succeeds).
An alignment report from IQ Tyres showing the before and after measurements — and confirming that the alignment was out of specification on the affected wheel — provides useful supporting evidence for a claim.
Protecting Your Alignment Between Services
Correct tyre inflation is the single most effective protection against pothole damage. An underinflated tyre has less air cushion between the rim and the road, which means the rim takes more of the impact force when you hit a pothole. Keeping tyres at the manufacturer's recommended pressure — checked monthly — reduces both the risk of pinch punctures and the severity of alignment shifts from pothole impacts.
Slowing down when you see a pothole is obvious advice, but it's worth stating: the energy transmitted to the suspension increases with the square of your speed. Hitting a pothole at 40 mph transmits four times the energy of hitting the same pothole at 20 mph.
Check Your Alignment After a Pothole
We use the Hunter HawkEye Elite — camera-based alignment measurement to 1/100th of a degree. Free initial check. Mitcham, South London.