City car · 2012–2021 cars
SEAT Mii reliability
The SEAT Mii fails 21.4% of first MOT tests, about average for its age and mileage, based on 56,123 DVSA MOT tests from 2022 to 2024.
Checking a SEAT Mii before you buy?
- first-time MOT fail rate (all cars: 28.4%)
- 21.4%
- first-time MOT fail rate (all cars: 28.4%)
- fails than cars of the same age and mileage
- 0% fewer
- fails than cars of the same age and mileage
- MOT tests analysed, 2022 to 2024
- 56,123
- MOT tests analysed, 2022 to 2024
- typical miles a year, from MOT readings
- 5,900
- typical miles a year, from MOT readings
MOT fail rate by age
How the SEAT Mii ages
Each point is the share of SEAT Miis of that age that failed their MOT first time, against all cars of the same age.
| Age at MOT (years) | SEAT Mii | All cars |
|---|---|---|
| 3 | 11% | 12.3% |
| 4 | 13.7% | 14.1% |
| 5 | 16.7% | 16.4% |
| 6 | 18.8% | 19.1% |
| 7 | 19.3% | 22.1% |
| 8 | 21.8% | 25.5% |
| 9 | 23.5% | 28.8% |
| 10 | 26.9% | 31.8% |
| 11 | 28.7% | 34.6% |
| 12 | 31.6% | 37.3% |
By year
The best and worst SEAT Mii years
2014 cars come out best and 2016 cars worst, once age and mileage are taken into account.
| First registered | Tests | Fail rate | Against same-age cars | Typical mileage |
|---|---|---|---|---|
| 2019 Mii | 3,353 | 11.5% | 2% more fails | 20,647 |
| 2018 Mii | 4,150 | 15.1% | 20% more fails | 24,720 |
| 2017 Mii | 4,865 | 17.2% | 15% more fails | 31,142 |
| 2016 Mii | 7,296 | 21.3% | 21% more fails | 37,553 |
| 2015 Mii | 8,863 | 20.5% | 1% fewer fails | 43,539 |
| 2014 Mii | 10,247 | 21.1% | 11% fewer fails | 50,269 |
| 2013 Mii | 11,605 | 25.9% | 4% fewer fails | 57,274 |
| 2012 Mii | 5,742 | 27.8% | 6% fewer fails | 61,737 |
Common problems
What fails most on a SEAT Mii
Its weak spot is seat belts and airbags: 334% more fails there than cars of the same age and mileage.
Fail rate by area
- Lights and electrics7.3%7% above avg
- Brakes5.5%31% above avg
- Windscreen, wipers and mirrors4.2%15% above avg
- Tyres3.9%26% below avg
- Suspension2.6%54% below avg
- Body, chassis and structure2.4%47% above avg
- Seat belts and airbags1.9%334% above avg
- Exhaust, emissions and leaks1.8%13% above avg
- Number plates and VIN0.2%28% below avg
Average for cars of the same age and mileage
Top MOT failures
- 1
Wiper blade not clearing windscreen 2.26% of tests
Wipers that do not clear the windscreen reduce visibility in rain, which is a safety risk, so replace them.
- 2
Service brake excessively binding 1.61% of tests
A brake that drags when released can overheat, wear quickly and waste fuel, so it needs prompt inspection.
- 3
Tyre tread below 1.6mm 1.6% of tests
Tread below 1.6mm is illegal and reduces grip in wet conditions, so the tyre must be replaced.
- 4
Position lamp not working 1.56% of tests
A failed position lamp makes the car harder to see in poor light and is illegal, so it must be repaired.
- 5
Airbag warning lamp shows fault 1.5% of tests
A lit airbag warning means the airbag system may not deploy in a crash, so it needs diagnosing and repairing.
- 6
Headlamp aim set too low 1.39% of tests
Headlamps aimed too low light the road poorly and reduce the driver's view ahead, especially at night.
- 7
Fuel filler cap ineffective 1.21% of tests
A faulty fuel cap can let fuel vapour escape and may trigger warning lights, so a replacement is usually simple.
- 8
Registration plate lamp not working 1.16% of tests
A dark number plate lamp makes the plate hard to read at night, which is illegal and must be fixed.
Most common advisories
Not a fail yet, but worth pricing in: these show up on a SEAT Mii's MOT certificate most often.
- Tyre slightly damaged or cracking11.91%
- Tyre worn close to legal limit10.9%
- Brake disc pitted or scored5.67%
- Brake pads wearing thin3.88%
- Suspension arm pin/bush showing wear3.27%
- Service brake slightly binding2.45%
Before you buy
What to check on a used SEAT Mii
- 1
Wiper blade not clearing windscreen
Wipers that do not clear the windscreen reduce visibility in rain, which is a safety risk, so replace them.
- 2
Service brake excessively binding
A brake that drags when released can overheat, wear quickly and waste fuel, so it needs prompt inspection.
- 3
Tyre tread below 1.6mm
Tread below 1.6mm is illegal and reduces grip in wet conditions, so the tyre must be replaced.
- 4
Position lamp not working
A failed position lamp makes the car harder to see in poor light and is illegal, so it must be repaired.
- 5
Every MOT since new
Look for the faults above coming back year after year: it shows how the car has been looked after.
- 6
The mileage record
A typical SEAT Mii covers about 5,900 miles a year. A big gap or a drop between MOTs is a warning sign.
- 7
Finance, stolen and write-off
The records the MOT can't show. A Full Check (£9.99) covers all three before you hand over any money.
Fuel types tested
- Petrol100%
- Diesel0%
- LPG0%
- Electric0%
Most common colours
White, Red, Black, Silver, Beige
Average engine size: 1.0 litres.
Compare
How the SEAT Mii compares with its rivals
| Model | Fail rate | Against same-age cars |
|---|---|---|
| Toyota iQ | 23% | 29% fewer MOT fails than the average car its age |
| SEAT Mii | 21.4% | about average for its age |
| Smart Fortwo Coupe | 34.8% | about average for its age |
| Abarth 595 | 18.6% | 16% more MOT fails than the average car its age |
| Citroën C2 | 47.7% | 19% more MOT fails than the average car its age |
| Fiat 500C | 31.5% | 27% more MOT fails than the average car its age |
| Chevrolet Spark | 44.8% | 46% more MOT fails than the average car its age |
Every city car ranked in the city car reliability index, or all SEAT models.
Questions
SEAT Mii questions, answered
Is the SEAT Mii reliable?
On MOT results, the SEAT Mii is about average: it fails 21.4% of first MOT tests, about average for its age and mileage. It ranks 9 of 43 city car models in our index.
What fails most on a SEAT Mii MOT?
The most common MOT failures on the SEAT Mii are wiper blade not clearing windscreen (2.26% of tests), service brake excessively binding (1.61% of tests), tyre tread below 1.6mm (1.6% of tests). By area, lights and electrics fails 7.3% of its tests.
Which SEAT Mii year is the most reliable?
Among years with 1,000+ tests, 2014 cars do best (11% fewer MOT fails than the average car its age) and 2016 cars do worst (21% more MOT fails than the average car its age).
How many miles does a SEAT Mii do a year?
A typical SEAT Mii covers about 5,900 miles a year, from the mileage recorded at its MOTs. Check the car you're looking at against that with a free mileage check.
How do I check a SEAT Mii before I buy it?
Enter its registration for a free check of its MOT history, mileage, ULEZ status and tax. Before you pay, a Full Check (£9.99) shows outstanding finance, stolen and write-off records.
Source: DVSA anonymised MOT test results, 2022 to 2024, class 4 vehicles aged 3 to 25, normal tests only. How we compare like with like: our methodology.
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