2021 BMW 8 Series — MOT failures & pass rate
3,640 MOT tests on the 2021 BMW 8 Series are in this dataset, and 88.3% of them passed. Against coupes & convertibles of a similar age (7.9% fail rate), the 2021 8 Series comes out 3.8pp worse. Failures cluster in tyres, lighting & signalling and road wheels.
What the MOT record shows
Tyres dominates the failure mix at 9.5% of all tests — 8.0 points clear of lighting & signalling, so it is the first thing to check.
At component level the recurring items are headlamp aim, tread depth and registration plates — headlamp aim alone was recorded 52 times.
Mileage matters less than usual here: the 2021 8 Series fails 11.5% of the time in the 0-30k band and 15.3% at 60-90k, a spread of only 3.8 points.
Advisories point at the next bill rather than this one: tyres was flagged on 16.6% of tests without failing them.
How it compares
Top failure categories
| # | Category | % of tests affected | Tests |
|---|---|---|---|
| 1 | Tyres | 9.5% | 347 |
| 2 | Lighting & signalling | 1.5% | 56 |
| 3 | Road wheels | 0.8% | 29 |
| 4 | Visibility | 0.7% | 25 |
| 5 | Other defects | 0.5% | 19 |
| 6 | Brakes | 0.4% | 13 |
Most common specific failures
The exact components most often recorded as failures — more specific than the categories above.
| # | Failure item | Times recorded |
|---|---|---|
| 1 | Headlamp aim | 52 |
| 2 | Tread depth | 42 |
| 3 | Registration plates | 29 |
| 4 | Side repeaters | 16 |
| 5 | Washers | 12 |
| 6 | Wipers | 11 |
Top advisory categories
Advisories aren't failures, but they flag work likely needed soon — useful when budgeting.
| # | Category | % of tests with advisory | Tests |
|---|---|---|---|
| 1 | Tyres | 16.6% | 605 |
| 2 | Other defects | 3.6% | 133 |
| 3 | Body, structure & corrosion | 1.9% | 68 |
| 4 | Brakes | 1.8% | 67 |
| 5 | Visibility | 1.7% | 62 |
| 6 | Road wheels | 1.1% | 40 |
Failure rate by mileage
Higher-mileage cars tend to fail more — often the most useful guide to real condition.
| Mileage band | Tests | Fail rate |
|---|---|---|
| 0-30k | 1,990 | 11.5% |
| 30-60k | 1,466 | 11.5% |
| 60-90k | 157 | 15.3% |
Failure rate by age
By fuel type
| Fuel | Tests | Fail rate |
|---|---|---|
| Petrol | 3,170 | 11.4% |
| Diesel | 470 | 13.6% |
Trend over time
| Dataset year | Tests | Fail rate |
|---|---|---|
| 2023 | 120 | 10.0% |
| 2024 | 1,800 | 12.7% |
| 2025 | 1,715 | 10.7% |
What to check before buying a 2021 8 Series
On a 2021 8 Series, tyres is what the MOT record says goes wrong most — it appeared in 9.5% of tests. Check these areas before you commit.
- Tyres (9.5% of tests): Usually a quick, known-cost fix, but check tread, age and uneven wear (which can hint at alignment or suspension issues). Typical repair: £50–£120 per tyre.
- Lighting & signalling (1.5% of tests): Often a cheap bulb, but persistent issues can mean wiring or corrosion in the units. Typical repair: £10–£150.
- Road wheels (0.8% of tests): Damaged or corroded wheels, missing/loose fixings — generally a moderate fix. Typical repair: £80–£250.
Repair costs are rough UK ballpark ranges to set expectations, not quotes — actual prices vary widely by car, parts and garage.
Frequently asked questions
How many 2021 BMW 8 Seriess pass their MOT?
88.3% of the 3,640 2021 BMW 8 Series MOT tests in this dataset passed — a 11.7% fail rate.
What is the most common MOT failure on a 2021 BMW 8 Series?
Tyres, recorded in 9.5% of tests, followed by lighting & signalling (1.5%).
Does the 2021 8 Series get worse with mileage?
Its MOT fail rate rises from 11.5% in the 0-30k band to 15.3% in the 60-90k band.
Methodology & source. Based on 3,640 MOT tests. Dataset: DVSA MOT testing data (2021,2022,2023,2024,2025). Data last updated 2026-07-27. Figures reflect MOT-testable defects only — read the methodology for how these are calculated and what they don't measure.