2021 Mazda 6 — MOT failures & pass rate
729 MOT tests on the 2021 Mazda 6 are in this dataset, and 93.5% of them passed. Large family cars of a similar age fail 10.4% of the time, so this is 4.0pp better than the group it competes with. Failures cluster in tyres, brakes and lighting & signalling.
What the MOT record shows
No single area dominates — tyres (3.0%) and brakes (2.2%) are close, so failures are spread across several systems rather than one weak point.
At component level the recurring items are headlamp aim, wipers and brake pads — headlamp aim alone was recorded 19 times.
Condition tracks the odometer closely. Failures run at 4.9% in the 0-30k band and 11.1% in the 60-90k band, a 6.2-point spread — more than double.
Brakes is the most common advisory, noted on 16.7% of tests — work that passed today but is likely due soon.
How it compares
Top failure categories
| # | Category | % of tests affected | Tests |
|---|---|---|---|
| 1 | Tyres | 3.0% | 22 |
| 2 | Brakes | 2.2% | 16 |
| 3 | Lighting & signalling | 2.1% | 15 |
| 4 | Visibility | 1.8% | 13 |
| 5 | Suspension | 0.4% | 3 |
| 6 | Body, structure & corrosion | 0.4% | 3 |
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 | 19 |
| 2 | Wipers | 15 |
| 3 | Brake pads | 12 |
| 4 | Service brake performance | 8 |
| 5 | Tread depth | 6 |
| 6 | Brake discs | 3 |
Top advisory categories
Advisories aren't failures, but they flag work likely needed soon — useful when budgeting.
| # | Category | % of tests with advisory | Tests |
|---|---|---|---|
| 1 | Brakes | 16.7% | 122 |
| 2 | Tyres | 16.6% | 121 |
| 3 | Other defects | 5.1% | 37 |
| 4 | Visibility | 4.0% | 29 |
| 5 | Suspension | 1.2% | 9 |
| 6 | Seat belts & restraints | 0.4% | 3 |
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 | 405 | 4.9% |
| 30-60k | 281 | 7.5% |
| 60-90k | 36 | 11.1% |
Failure rate by age
Trend over time
| Dataset year | Tests | Fail rate |
|---|---|---|
| 2024 | 351 | 6.0% |
| 2025 | 359 | 6.4% |
What to check before buying a 2021 6
The failure pattern for this year is specific enough to inspect against: tyres accounted for 3.0% of tests. Start there.
- Tyres (3.0% 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.
- Brakes (2.2% of tests): Pads/discs are routine wear; binding, imbalance or corroded pipes are more serious — test for pulling under braking. Typical repair: £100–£350 per axle.
- Lighting & signalling (2.1% of tests): Often a cheap bulb, but persistent issues can mean wiring or corrosion in the units. Typical repair: £10–£150.
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 Mazda 6s pass their MOT?
93.5% of the 729 2021 Mazda 6 MOT tests in this dataset passed — a 6.5% fail rate.
What is the most common MOT failure on a 2021 Mazda 6?
Tyres, recorded in 3.0% of tests, followed by brakes (2.2%).
Does the 2021 6 get worse with mileage?
Its MOT fail rate rises from 4.9% in the 0-30k band to 11.1% in the 60-90k band.
Methodology & source. Based on 729 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.