MotR
Official DVSA Data · Updated 2026

Common MOT Failures UK

Around one in three UK vehicles fails its MOT on the first attempt. Most failures are avoidable. This guide breaks down every major failure category — what causes them, what they cost to fix, and exactly how to prevent them.

Official UK dataFree to useInstant resultsNo account needed
Common MOT Failures UK

Quick Answer

Around one third of UK cars fail their MOT on first attempt. The five most common failure categories — lighting (18%), brakes (12%), tyres (10%), suspension (9%), and windscreen/visibility (6%) — account for over half of all failures. Most are preventable with a 10-minute pre-test walk-around check before the appointment.
The numbers

MOT Failure Statistics by Category

The DVSA publishes annual statistics on MOT test results. The table below shows the main failure categories by frequency, typical repair cost range, and whether the repair is commonly DIY-accessible. Lighting faults top the list every year — and most take minutes to fix for under £10.

Failure categoryShare of all failuresTypical repair costDIY possible?
Lighting & signalling~18–20%£5–£80Often yes
Brakes~12–14%£80–£600+No
Tyres~10–12%£80–£550No
Suspension & steering~9–11%£60–£800+No
Windscreen & visibility~6–8%£20–£300Partially
Exhaust & emissions~6–7%£50–£1,200No
Seatbelts & restraints~3–4%£50–£300No
Bodywork & structure~3–5%£200–£1,500+No
Number plates~2–3%£10–£30Yes
Wipers & washers~2–3%£10–£40Yes

Source: DVSA annual test data. Percentages are approximate and vary year to year. Repair costs are UK estimates for independent garages.

The specific failures

The Top 10 Individual MOT Failure Items

Within the broad categories, these are the ten most frequently recorded specific failure items in UK MOT tests. Many appear preventable with basic pre-test preparation.

01Lighting

Direction indicator lamp defective

Cost: £5–£25

Bulb replacement. DIY in 10 minutes.

02Lighting

Headlamp aim incorrect

Cost: Free–£30

Adjusted at test centre or with adjustment screws.

03Lighting

Stop lamp not working

Cost: £5–£25

Bulb or LED cluster replacement.

04Tyres

Tyre tread below 1.6mm legal limit

Cost: £80–£140 per tyre

Tyre replacement. Cannot DIY safely.

05Brakes

Front brake pad/disc worn beyond limit

Cost: £120–£280 per axle

Garage replacement — safety critical.

06Visibility

Windscreen crack in driver's critical zone

Cost: £20–£300

Chip repair or full screen replacement.

07Signalling

Horn not working

Cost: £0–£80

Check fuse first. Horn unit replacement if needed.

08Identification

Number plate illegible or damaged

Cost: £10–£30

Replacement plate. DIY in minutes.

09Visibility

Front wiper blade not clearing screen

Cost: £15–£35

Blade replacement. DIY in 5 minutes.

10Suspension

Rear suspension arm bush worn or deteriorated

Cost: £150–£350

Garage job — press-fit bush replacement.

Prevent the avoidable

Pre-MOT Check: 10 Things to Do the Week Before

A methodical walk-around inspection the week before your MOT appointment costs nothing and prevents the majority of avoidable failures. The DVSA's own guidance confirms most test failures come from items the driver could have spotted themselves.

Check every external light — park in front of a wall or garage door and walk around the car at night
Check brake lights — use a reflection in a wall, or ask someone to stand behind while you press the pedal
Check all four tyre tread depths with a 20p coin — outer band is 1.6mm; if you can see it, they will fail
Check tyre sidewalls for bulges, cuts, or visible cord — these are automatic failures
Check windscreen for chips or cracks in the A-zone (driver's line of sight) — chips over 10mm fail
Test horn operation — a non-working horn is an instant and embarrassing failure
Check both front wiper blades — smearing, chattering, or torn rubber will fail the visibility test
Check the handbrake — it must hold the car on an incline with reasonable force
Check brake performance — in an empty car park, test full-stop from 20mph for even, straight stopping
Ensure number plates are clean, legible, and correctly coloured — yellow rear, white front
The cluster

Cluster: In-Depth Guides by Failure Category

Brake MOT Failures

Most dangerous category — causes, costs, prevention

Open

Tyre MOT Failures

Tread, condition, sidewall — what fails and why

Open

Suspension MOT Failures

Bushes, dampers, joints — the most complex failures

Open

Lighting MOT Failures

Most common category — cheapest to prevent

Open

Windscreen MOT Failures

Chips, cracks, zones — exactly what fails

Open

Exhaust MOT Failures

Blowing, corroded, and emissions failures

Open

Emissions MOT Failures

Cat, lambda sensor, smoke — what the test measures

Open

Rust MOT Failures

Structural corrosion — the most expensive failures

Open

MOT Failure Costs UK

Complete repair cost guide for every category

Open
Keep reading

Related MOT Tools & Guides

MOT Status Check

Is your MOT currently valid?

Open

MOT History Checker

Full test record, advisories, failures

Open

MOT Due Date Check

When exactly is my MOT due?

Open

What Fails an MOT

Official DVSA failure standards explained

Open

How to Pass Your MOT

Pre-test preparation guide

Open

Complete MOT Guide

Everything about the UK MOT test

Open

MOT Advisories

What advisories mean and cost

Open

MOT Risk Checker

Predict your failure risk before the test

Open

Pre-MOT Checklist

10-minute walk-around before your test

Open

Repair Cost Guide

What each MOT failure costs to fix

Open
Questions & answers

Frequently Asked Questions

What is the most common MOT failure in the UK?
Lighting and signalling faults are the single most common category, accounting for around 18–20% of all MOT failures. Within this category, blown bulbs, defective direction indicators, and brake lights that don't work are the most frequent. Most lighting failures take minutes to fix at home for under £10.
How many cars fail their MOT each year?
Approximately 30 million vehicles are tested annually in the UK. Around one third — close to 10 million — fail on first attempt. The DVSA publishes annual statistics showing failure reasons by category. Lighting faults, tyre defects, and brake failures consistently top the list.
What happens if I fail my MOT?
If your car fails its MOT and was tested before the current certificate expired, you can drive it away — but only to get it repaired. If it receives a Dangerous defect, you cannot drive it at all. You have 10 working days to return for a free partial retest covering only the failed items, at the same test centre.
Can I still drive after an MOT failure?
Depends on the type of failure. A Major failure means the car does not meet minimum safety standards — you can technically drive it to get it repaired, but you risk prosecution if stopped. A Dangerous failure means you cannot drive it at all. If your previous certificate is still valid and you receive a Dangerous or Major defect, technically it is still legal to drive — but inadvisable and potentially prosecutable.
How can I avoid an MOT failure?
Most MOT failures are preventable. Check all lights (front, rear, indicators, brake lights) before the test. Check tyre tread depth with a 20p coin — the outer band on a 20p is 1.6mm. Confirm brakes feel even and responsive. Check windscreen for chips larger than 10mm in the driver's line of sight. Most testers note that a 10-minute pre-test walk-around catches 60% of avoidable failures.
Is a fresh MOT guaranteed to find all problems?
No. MOT tests check only safety-critical items against minimum legal standards on the day of the test. The engine, gearbox, clutch, air conditioning, and many mechanical systems are not inspected. A car can pass an MOT and have expensive repairs imminent. Always use MOT history plus a pre-purchase inspection from an independent mechanic for significant purchases.
What is the most expensive common MOT failure?
Structural corrosion repairs are typically the most expensive common failure. Welding corroded subframe mounts or chassis members can cost £500–£1,500+. Catalytic converter failures can cost £300–£1,000 depending on the car. Brake system overhauls (seized callipers, corroded brake lines) run to £200–£600.
Check before your test

Free MOT Tools

MOT Status Check

Is your current MOT valid?

Open

MOT History Checker

Every test, advisory, failure and mileage reading

Open

MOT Due Date Check

Exactly when is your MOT due?

Open

MOT Risk Checker

Predict your failure risk before the test

Open
SR

Ste Robinson

Founder, MotR · Last reviewed 12 June 2026

Ste Robinson is the founder of MotR, helping UK drivers check MOT history, tax status, vehicle records and ownership information using official DVLA and DVSA data.

Check Your MOT Status & History Free

See every past test, advisory, failure, and mileage reading — official DVSA data, free in 30 seconds.

MOT failure statistics sourced from DVSA annual test data. Percentages are approximate and vary year to year. Repair costs are UK estimates for independent garages, 2026.

Keep reading

Brake MOT Failures

The most safety-critical failure category — causes, repair costs, and how to pass first time.

Open