Seat Mii
From 25,929 MOT tests. Above average for its class.
Common MOT failure categories
Pass rate by registration year
Newer Miis fare better: 2019 models pass at 88.2% vs 75.7% for 2012.
What goes wrong?
The most common MOT failure reasons are significant brake effort recorded with no brake applied indicating a binding brake, tyre tread depth not in accordance with the requirements, a suspension pin and bush or joint excessively worn. The top issue, significant brake effort recorded with no brake applied indicating a binding brake, caused 574 failures in 2024. Checking tread depth (1.6mm legal minimum, 3mm recommended) before your test can save an unnecessary fail. You can check prices at Black Circles if you need replacements. If you need repairs before retesting, sites like BookMyGarage let you compare local prices.
| significant brake effort recorded with no brake applied indicating a binding brake | 574 |
| tyre tread depth not in accordance with the requirements | 421 |
| a suspension pin, bush or joint excessively worn | 384 |
| a tyre seriously damaged | 362 |
| emissions levels exceed default limits | 282 |
| wiper blade missing or obviously not clearing the windscreen | 276 |
| fuel system leaking, or missing or ineffective filler cap | 230 |
| a lamp missing, inoperative or in the case of a multiple light source more than 1/2 not functioning | 229 |
| lambda coefficient outside the default limits or the range specified by the manufacturer | 218 |
| the aim of a headlamp is not within limits laid down in the requirements | 214 |
How serious are these failures?
Not all MOT failures are equal. 41.4% of failures are serious: 41.4% are safety issues (brakes, steering, tyre damage) and 0% could actually leave you stranded. That's close to the 44.4% average across all models. When it does fail, the average repair bill is around £81.
Seat Mii on UK roads
The fleet is shrinking: 106 scrapped or exported in the past year with only 1 newly registered, a net loss of 105.
Quarterly breakdown
| Quarter | On road | SORN | New | Gone | Net |
|---|---|---|---|---|---|
| 2025 Q3 | 17,940 | 201 | +1 | -46 | -45 |
| 2025 Q2 | 18,003 | 183 | +0 | -60 | -60 |
| 2025 Q1 | 18,054 | 192 | +0 | -0 | +16 |
| 2024 Q4 | 18,057 | 173 | +0 | -0 | +2 |
| 2024 Q3 | 18,075 | 153 | +0 | -45 | -45 |
| 2024 Q2 | 18,119 | 154 | +0 | -60 | -60 |
| 2024 Q1 | 18,167 | 166 | +0 | -64 | -64 |
| 2023 Q4 | 18,251 | 146 | +0 | -1 | -1 |
15 variants on the road
| Variant | Fuel | Licensed | Share |
|---|---|---|---|
| Mii Toca | Petrol | 3,061 | 17% |
| Mii Design | Petrol | 2,986 | 17% |
| Mii I-Tech | Petrol | 1,831 | 10% |
| Mii By Mango | Petrol | 1,722 | 10% |
| Mii Se | Petrol | 1,695 | 9% |
| Mii Fr-Line | Petrol | 1,409 | 8% |
| Mii Ev | Battery Electric | 1,307 | 7% |
| Mii Sport | Petrol | 1,261 | 7% |
| Mii S Ac | Petrol | 844 | 5% |
| Mii S | Petrol | 495 | 3% |
| Mii Se Auto | Petrol | 429 | 2% |
| Mii Ecomotive | Petrol | 324 | 2% |
| Mii By Cosmopolitan | Petrol | 296 | 2% |
| Mii Se Technology | Petrol | 136 | <1% |
| Mii By Mango Limited Edition | Petrol | 74 | <1% |
Source: DfT vehicle licensing statistics, 2025 Q3. Crown copyright, OGL v3.0.
By registration year
| Year | Pass rate | Top failures |
|---|---|---|
| 2019 | 88.2% | a tyre seriously damaged, tyre tread depth not in accordance with the requirements |
| 2018 | 85.9% | a tyre seriously damaged, wiper blade missing or obviously not clearing the windscreen |
| 2017 | 82.8% | a tyre seriously damaged, a suspension pin, bush or joint excessively worn |
| 2016 | 81.1% | a suspension pin, bush or joint excessively worn, a lamp missing, inoperative or in the case of a multiple light source more than 1/2 not functioning |
4 earlier years
| 2015 | 81.1% | emissions levels exceed default limits, significant brake effort recorded with no brake applied indicating a binding brake |
| 2014 | 79.9% | significant brake effort recorded with no brake applied indicating a binding brake, a suspension pin, bush or joint excessively worn |
| 2013 | 77.3% | significant brake effort recorded with no brake applied indicating a binding brake, tyre tread depth not in accordance with the requirements |
| 2012 | 75.7% | significant brake effort recorded with no brake applied indicating a binding brake, an srs malfunction indicator lamp (mil) indicates a system malfunction |
Typical mileage
Half of all Miis tested had between 31,126 and 70,406 miles on the clock.
At 49,431 median miles, the Mii has 0.039 failures per 10,000 miles driven.
Other Seat models
| Seat Ibiza | 74.7% |
| Seat Leon | 80.8% |
| Seat Ateca | 89.9% |
| Seat Arona | 87.2% |
| Seat Alhambra | 78.8% |
Common questions
What is the Seat Mii MOT pass rate?
The Seat Mii has a 80.5% MOT pass rate based on 25,929 real MOT tests. This is above the national average.
What are common MOT failures on a Seat Mii?
The most common MOT failure on the Seat Mii is significant brake effort recorded with no brake applied indicating a binding brake, which caused 574 failures. Other common issues include tyre tread depth not in accordance with the requirements.
How many Seat Miis are on UK roads?
There are 17,940 Seat Miis currently licensed on UK roads, with 201 on SORN.
What is the typical mileage of a Seat Mii at MOT?
The median mileage at MOT for a Seat Mii is 49,431 miles. The middle 50% of vehicles tested have between 31,126 and 70,406 miles.
Buying a used Mii?
Start with the free tools. Look up the specific vehicle's MOT history on GOV.UK The mileage at each test will show if it's been wound back, and the advisory history tells you what's wearing. Cross-reference that against the typical failures above to see if anything looks unusual for this model.
The free data won't tell you about outstanding finance, theft markers, or write-off history. For that, you need a vehicle history check This is especially important on a private sale where you have fewer legal protections.
With a 80.5% pass rate and an average repair bill of £81 when things go wrong, budget accordingly.
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MOT data from DVSA anonymised test results, 2024 test year. Fleet data from DfT vehicle licensing statistics. Crown copyright, OGL v3.0. MOT pass rates are statistical summaries of test outcomes, not assessments of individual vehicle safety or condition. Always inspect a vehicle and check its full MOT history before purchasing. See terms of use.