SEAT Mii MOT Pass Rate
Overall pass rate across all manufacture years, based on 117,455 real MOT test results. Failure rate: 19.2%.
Data from official DVSA MOT testing records
SEAT Mii MOT Reliability Overview
The SEAT Mii is a well-known vehicle in the UK, with 117,455 MOT test results recorded in our database spanning 8 manufacture years. It has an overall MOT pass rate of 80.8% and a failure rate of 19.2%, which is well above the UK average of approximately 37%.
Based on this data, the SEAT Mii earns a "Excellent" reliability rating. The average SEAT Mii presents for MOT with approximately 38,858 miles on the clock. Manufacture year matters: 2019 models achieve the highest pass rate at 89.2%, while 2012 models have the lowest at 77.0%. This 12.2 percentage point difference suggests notable variation in build quality or component durability across production years.
The most common MOT failure for the SEAT Mii is Tyres, affecting 14.2% of all tests. Tyre failures include tread depth below the legal minimum of 1.6mm, cuts, bulges, exposed cords, and incorrect tyre pressure. Tyres are one of the most common and easiest-to-prevent MOT failures. The second most common issue is Brakes at 12.1%. Lamps, reflectors and electrical equipment rounds out the top three at 7.6%. Together, these top 3 failure categories account for a significant portion of all MOT failures for this model.
Top failures across all manufacture years combined. Individual year pages may show different top failures.
What Fails Most
Best Year to Buy
Based on MOT data, 2019 models have the highest pass rate at 87.3%.
Based on 2024 MOT test results only — the most recent data available. "Built" = year of manufacture. Cars need their first MOT at 3 years old, so the newest cars shown are from ~3 years ago.
Bar chart showing pass rate by manufacture year from 2012 to 2019
📈 How Each Vintage Ages
Tracking how each manufacture year's MOT pass rate changes as the car ages. Showing 8 vintages — click year chips to highlight.
Multi-line chart showing how different SEAT Mii vintages degrade over time, from age 2 to 20 years.
Only vintages with 100+ tests in at least 3 different test years are shown. Fleet average is the UK-wide pass rate for all cars at each age.
📉 How Age Affects Reliability
MOT failure rate by vehicle age for the SEAT Mii. The dashed red line marks when the manufacturer warranty typically expires (3 years).
Line chart showing MOT failure rate by vehicle age from 3 to 12 years, with warranty expiry marked at 3 years.
💡 What does the warranty cliff mean?
The SEAT Mii shows a moderate increase in MOT failures after warranty. The 46% increase is typical — plan for gradual maintenance cost increases. Peak failure occurs at age 12 (29.7% fail rate).
Note: pass rates may improve for very old vehicles due to survivorship bias — only well-maintained cars remain on the road.
* High Fail Rate badge indicates an MOT pass rate below 65% (failure rate above 35%).
What Fails on This Car?
Click a category to see specific failure items.
View as table
| Rank | Failure Category | Rate (%) | Count |
|---|---|---|---|
| 1 | Tyres | 14.2% | 16,651 |
| 2 | Brakes | 12.1% | 14,199 |
| 3 | Lamps, Reflectors And Electrical Equipment | 8.8% | 10,407 |
| 4 | Visibility | 5.4% | 6,369 |
| 5 | Suspension | 3.4% | 3,976 |
| 6 | Seat Belts And Supplementary Restraint Systems | 2.2% | 2,585 |
| 7 | Noise, Emissions And Leaks | 2.1% | 2,452 |
| 8 | Body, Chassis, Structure | 1.9% | 2,179 |
| 9 | Non-component Advisories | 1.8% | 2,102 |
| 10 | Driver's View Of The Road | 1.1% | 1,283 |
| 11 | Identification Of The Vehicle | 0.4% | 475 |
| 12 | Road Wheels | 0.4% | 454 |
| 13 | Steering | 0.2% | 241 |
Failures per 10,000 Miles
avg. 38,858 miFor every 10,000 miles driven, this shows what percentage of MOT tests fail for each category. This accounts for how far cars are actually driven, not just raw pass/fail counts.
View as table
| Category | Rate / 10K mi | Raw % | Count |
|---|---|---|---|
| Tyres | 3.65 | 14.2% | 16,651 |
| Brakes | 3.11 | 12.1% | 14,199 |
| Lamps & Electrical | 2.28 | 8.8% | 10,407 |
| Visibility | 1.68 | 6.5% | 7,652 |
| Suspension | 0.87 | 3.4% | 3,976 |
| Seat Belts | 0.56 | 2.2% | 2,585 |
| Noise, emissions and leaks | 0.54 | 2.1% | 2,452 |
| Body & Structure | 0.48 | 1.9% | 2,179 |
| Non-component advisories | 0.46 | 1.8% | 2,102 |
| Identification of the vehicle | 0.10 | 0.4% | 475 |
| Wheels | 0.10 | 0.4% | 454 |
| Steering | 0.05 | 0.2% | 241 |
🚗 Similar Cars to Consider
Mileage at MOT
The average SEAT Mii has 38,858 miles when tested for MOT.
📊 Mileage-Adjusted Failure Rate
How often this car fails MOT relative to how much it's driven — a fairer comparison than raw pass rate.
The SEAT Mii has a mileage-adjusted failure rate of 4.94% per 10,000 miles driven. The average across all makes is 5.38%, so this model is better than average.
About SEAT Mii MOT Data
The SEAT Mii is a well-known vehicle in the UK, with 117,455 MOT test results recorded in our database spanning 8 manufacture years. It has an overall MOT pass rate of 80.8% and a failure rate of 19.2%, which is well above the UK average of approximately 37%.
For SEAT Mii owners, these results suggest a reliable vehicle that generally passes its MOT without major issues. Focus your pre-MOT checks on tyres and brakes for the best chance of a first-time pass. Use our detailed year-by-year breakdown and failure analysis below to understand how your specific Mii is likely to perform.
Tyres — 14.2% of failures
Tyres issues account for 14.2% of MOT failures on the SEAT Mii. Tyre failures include tread depth below the legal minimum of 1.6mm, cuts, bulges, exposed cords, and incorrect tyre pressure. Tyres are one of the most common and easiest-to-prevent MOT failures. Typical repair costs: £50–200 per tyre. Pre-MOT check: Check tread depth with a 20p coin — if the outer band is visible, the tyre is too worn. Look for bulges, cuts, or embedded objects. Ensure all tyres match the recommended size and load rating.
Brakes — 12.1% of failures
Brakes issues account for 12.1% of MOT failures on the SEAT Mii. Brake-related failures include worn brake pads, corroded brake discs, leaking brake lines, and faulty brake servos. These are safety-critical components — any brake deficiency will result in an MOT fail. Typical repair costs: £150–400. Pre-MOT check: Listen for squealing or grinding noises. Check brake pedal feel — if it feels spongy or goes to the floor, have the system inspected immediately. Look at brake pad thickness through the wheel spokes (minimum 3mm).
Lamps, reflectors and electrical equipment — 7.6% of failures
Lamps, reflectors and electrical equipment issues account for 7.6% of MOT failures on the SEAT Mii. Lighting failures cover all external lights: headlights, tail lights, brake lights, indicators, fog lights, and reflectors. A single blown bulb will cause an MOT fail. This is one of the most preventable failure categories. Typical repair costs: £5–50. Pre-MOT check: Walk around the car and check every light — headlights (dipped and main beam), side lights, tail lights, brake lights, indicators, hazard lights, reverse light, rear fog light, and number plate lights. Replace any blown bulbs before the test.
Frequently Asked Questions
What is the MOT pass rate for the SEAT Mii?
Based on 117,455 MOT tests in our database, the SEAT Mii has an overall pass rate of 80.8% (19.2% fail rate).
What are the most common MOT failures on a SEAT Mii?
The top 3 reasons a SEAT Mii fails its MOT are: 1. Tyres (14.2%), 2. Brakes (12.1%), 3. Lamps, reflectors and electrical equipment (7.6%). Check these areas before booking your MOT.
Is the SEAT Mii reliable?
With a 19.2% MOT failure rate, the Mii is more reliable than average compared to the UK average of ~40%.
What should I check before an MOT on my SEAT Mii?
Based on failure data, focus on: Tyres (14.2%); Brakes (12.1%); Lamps, reflectors and electrical equipment (7.6%). These are the areas most likely to cause a fail. Also check all lights, tyres (minimum 1.6mm tread), and windscreen condition — these are quick wins that apply to all cars.
Based on DVSA anonymised MOT test data (2005–2024). Crown copyright, Open Government Licence v3.0.