2021 Porsche Boxster — MOT failures & pass rate
The 2021 Porsche Boxster passed 96.7% of its 579 recorded MOT tests. That is 4.7 percentage points better than coupes & convertibles of a similar age, which fail at 8.0%. Failures cluster in tyres, lighting & signalling and suspension.
What the MOT record shows
No single area dominates — tyres (2.3%) and lighting & signalling (1.0%) are close, so failures are spread across several systems rather than one weak point.
At component level the recurring items are headlamp aim, registration plates and shock absorbers — headlamp aim alone was recorded 6 times.
Tyres is the most common advisory, noted on 8.1% of tests — work that passed today but is likely due soon.
How it compares
Top failure categories
| # | Category | % of tests affected | Tests |
|---|---|---|---|
| 1 | Tyres | 2.3% | 13 |
| 2 | Lighting & signalling | 1.0% | 6 |
| 3 | Suspension | 0.5% | 3 |
| 4 | Other defects | 0.4% | 2 |
| 5 | Brakes | 0.2% | 1 |
| 6 | Emissions & environmental | 0.2% | 1 |
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 | 6 |
| 2 | Registration plates | 3 |
| 3 | Shock absorbers | 2 |
| 4 | Tread depth | 2 |
| 5 | Linkage ball joint dust cover | 1 |
| 6 | Catalyst emissions | 1 |
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 | 8.1% | 47 |
| 2 | Other defects | 2.9% | 17 |
| 3 | Visibility | 1.7% | 10 |
| 4 | Brakes | 0.4% | 2 |
| 5 | Road wheels | 0.4% | 2 |
| 6 | Suspension | 0.4% | 2 |
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 | 535 | 2.8% |
| 30-60k | 41 | 9.8% |
Failure rate by age
Trend over time
| Dataset year | Tests | Fail rate |
|---|---|---|
| 2024 | 270 | 2.2% |
| 2025 | 295 | 4.1% |
What to check before buying a 2021 Boxster
The failure pattern for this year is specific enough to inspect against: tyres accounted for 2.3% of tests. Start there.
- Tyres (2.3% 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 (1.0% of tests): Often a cheap bulb, but persistent issues can mean wiring or corrosion in the units. Typical repair: £10–£150.
- Suspension (0.5% of tests): Worn drop links, bushes, springs or shocks — listen for knocks over bumps and check for uneven tyre wear. Typical repair: £150–£450 per corner.
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 Porsche Boxsters pass their MOT?
96.7% of the 579 2021 Porsche Boxster MOT tests in this dataset passed — a 3.3% fail rate.
What is the most common MOT failure on a 2021 Porsche Boxster?
Tyres, recorded in 2.3% of tests, followed by lighting & signalling (1.0%).
Does the 2021 Boxster get worse with mileage?
Its MOT fail rate rises from 2.8% in the 0-30k band to 9.8% in the 30-60k band.
Methodology & source. Based on 579 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.