1,246 tests in 2025
SEAT Mii Electric reliability and MOT pass rate
90.2% passed first time. The 9.8% fail rate is 12.8 points better than the all-car average, on a median example 4 years old with 22,977 miles.
Electric versions only, by DVSA’s fuel record for each test. Petrol, diesel and hybrid versions are on the SEAT Mii page.
Pass rate
90.2%
22.6% of all cars failed; 9.8% of these did.
Fixed on the day
3%
Passed after a defect was put right during the visit.
Median at test
22,977 mi
4 years old.
Fail rate by age
| Age at test | Tests | Fail rate |
|---|---|---|
| 3-5 years | 1,246 | 9.8% |
| 6-9 years | 0 | — |
| 10-13 years | 0 | — |
| 14+ years | 0 | — |
What the Mii Electric fails on
Share of failed tests with at least one fail item in each DVSA inspection section. A test can fail in several sections at once.
- Tyres59 dangerous59%
- Brakes3 dangerous18.9%
- Lamps, reflectors and electrical equipment17.2%
- Suspension2 dangerous13.9%
- Visibility8.2%
- Identification of the vehicle2.5%
- Seat belts and supplementary restraint systems1.6%
- Body, chassis, structure0.8%
Is the Mii Electric getting worse?
The fail rate fell 1.4 points to 9.8% from 2024 to 2025 while the median one tested aged 1 year, which is about what ageing alone predicts (1 point). Read it as the fleet getting older rather than the model changing.
| Year | Tests | Median age | Fail rate | All cars | |
|---|---|---|---|---|---|
| 2024 | 1,120 | 3 | 11.2% | 23.2% | |
| 2025 | 1,247 | 4 | 9.8% | 22.6% |
Fail rate is first attempts at class 4 tests. Median age is the age of a typical Mii Electric at its test that year, and it is the number to watch: across the whole fleet each extra year of age adds roughly 1.9 points to the fail rate, so a model whose age and fail rate rise together is simply getting older.
The exact defects that fail it
Every failure item DVSA recorded against a Mii Electric in 2025, counted by how many tests each one appeared on.
- 1Condition: has a bulge, caused by separation or partial failure of its structure37 tests
- 2Condition: has a cut in excess of the requirements deep enough to reach the ply or cords19 tests
- 3Service brake performance: excessively binding9 tests
- 4Linkage ball joints: ball joint excessively worn8 tests
- 5Registration plate lamp(s): inoperative in the case of a single lamp or all lamps5 tests
- 6Service brake imbalance: across an axle5 tests
- 7Washers: provides insufficient washer liquid5 tests
- 8Condition: has a lump, caused by separation or partial failure of its structure4 tests
What wears out first
Advisories are the tester flagging wear that is still legal. A typical Mii Electric collects 1.77 of them per test, and these are the ones that come up most. Treat it as the running-repairs list for the next year or two.
- 1Condition: has a tear, caused by separation or partial failure of its structure180 tests
- 2Tread depth: tread depth below requirements of 1.6mm118 tests
- 3Brake discs: in such a condition that it is seriously weakened55 tests
- 4Non-component advisories: Nail in tyre30 tests
- 5Condition: has a cut in excess of the requirements deep enough to reach the ply or cords19 tests
- 6Non-component advisories: Child Seat fitted not allowing full inspection of adult belt19 tests
- 7Pins and bushes: pin or bush excessively worn15 tests
- 8Tread depth: tread pattern not visible over the whole tread area when minimum depth required is 1.0mm13 tests
Questions
What is the SEAT Mii Electric MOT pass rate?
90.2% of the 1,246 SEAT Mii Electric first-attempt MOTs in 2025 passed. The fail rate of 9.8% compares with 22.6% across all cars. A further 3% passed after a defect was fixed during the test visit.
What does a SEAT Mii Electric usually fail on?
The single most common failure is "Condition: has a bulge, caused by separation or partial failure of its structure", recorded on 37 failed tests, followed by "Condition: has a cut in excess of the requirements deep enough to reach the ply or cords" and "Service brake performance: excessively binding". By section, tyres appears in 59% of failures, brakes appears in 18.9% of failures, lamps, reflectors and electrical equipment appears in 17.2% of failures.
Does age change the odds?
Sharply. At 3 to 5 years old the fail rate was 9.8%; at 3-5 years it was 9.8%. The median SEAT Mii Electric tested in 2025 was 4 years old with 22,977 miles.
Is the SEAT Mii Electric getting less reliable?
The fail rate fell 1.4 points to 9.8% from 2024 to 2025 while the median one tested aged 1 year, which is about what ageing alone predicts (1 point). Read it as the fleet getting older rather than the model changing.
First-attempt class 4 tests, 2025, from DVSA’s anonymised MOT data (OGL v3, retrieved 2026-09-12). DVSA records newer cars trim by trim; this page adds every Mii Electric trim together. Year-on-year figures come from the same DVSA extracts for 2026 and earlier years. Full method on the pass rates hub.
Other SEAT models
Checking a particular Mii Electric?
The odds above are the model. The car in front of you has its own record: every test, every advisory, the mileage at each one.
Due a test? Find an approved MOT station near you.