2018 SEAT Mii MOT pass rate: 88.8% (3,743 tests)
Is the 2018 Mii getting worse?
Pass rate of 2018-registered cars across recent test years:
| Test year | Pass rate | |
|---|---|---|
| 2023 | 91.0% +3.0 vs same-age |
|
| 2024 | 88.0% +1.8 vs same-age |
|
| 2025 | 87.3% +2.5 vs same-age |
The raw rate normally falls as cars age. The “vs same-age” figure compares this cohort with all UK cars registered in the same year, so normal ageing is not mistaken for a bad model year.
What fails on a 2018 Mii
| # | System | Defects recorded | Share |
|---|---|---|---|
| 1 | Tyres | 208 | 26.0% |
| 2 | Lamps, reflectors and electrical equipment | 142 | 17.8% |
| 3 | Brakes | 141 | 17.6% |
| 4 | Visibility | 128 | 16.0% |
| 5 | Suspension | 80 | 10.0% |
| 6 | Noise, emissions and leaks | 77 | 9.6% |
All Mii years compared
| Registration year | Tests | Pass rate | Vs same-age | Median mileage |
|---|---|---|---|---|
| 2012 | 5,206 | 77.8% | +6.6 pts | 66,377 |
| 2013 | 10,381 | 79.0% | +5.7 pts | 61,678 |
| 2014 | 9,192 | 82.0% | +6.2 pts | 54,841 |
| 2015 | 7,947 | 82.4% | +3.7 pts | 48,300 |
| 2016 | 6,604 | 82.7% | +1.3 pts | 42,446 |
| 2017 | 4,384 | 86.4% | +2.4 pts | 36,112 |
| 2018 (this page) | 3,743 | 88.8% | +2.4 pts | 29,527 |
| 2019 | 3,866 | 91.5% | +3.1 pts | 23,043 |
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FAQs
Is a 2018 SEAT Mii reliable?
2018-registered examples passed 88.8% of their MOT tests (3,743 tests, 2023–2025), +2.4 points versus all UK cars registered in the same year. At roughly 8 years old with a median 29,527 miles, condition now varies car by car — always check the individual MOT history.
What mileage is too high for a 2018 Mii?
The median tested example shows 29,527 miles. Anything far beyond that isn't automatically bad — a motorway-mile car with consistent service records often beats a low-mileage school-run car — but price accordingly and scrutinise the mileage trail for gaps or drops.
Source: DVSA Anonymised MOT tests and results, 2023–2025 extracts (96 million Class 4 initial tests; retests excluded). Only vehicles old enough for a routine first MOT are included. Age-adjusted figures compare the model-year cohort with all vehicles of the same registration year tested in the same calendar year. Contains public sector information licensed under OGL v3.0.