2021 Kia Stonic — MOT failures & pass rate
The 2021 Kia Stonic passed 94.0% of its 12,889 recorded MOT tests. Small SUVs of a similar age fail 7.2% of the time, so this is 1.2pp better than the group it competes with. Failures cluster in visibility, tyres and lighting & signalling.
What the MOT record shows
No single area dominates — visibility (3.8%) and tyres (2.1%) are close, so failures are spread across several systems rather than one weak point.
At component level the recurring items are wipers, brake pads and headlamp aim — wipers alone was recorded 446 times.
Condition tracks the odometer closely. Failures run at 4.5% in the 0-30k band and 13.2% in the 60-90k band, a 8.7-point spread — more than double.
The hybrid cars hold up better: 5.3% fail against 7.2% for petrol, a 1.9-point gap across 12,886 tests.
Tyres is the most common advisory, noted on 13.8% of tests — work that passed today but is likely due soon.
The trend is worsening — 3.6% of tests failed in 2023 against 6.8% in 2025, the usual pattern as a fleet ages.
How it compares
Top failure categories
| # | Category | % of tests affected | Tests |
|---|---|---|---|
| 1 | Visibility | 3.8% | 483 |
| 2 | Tyres | 2.1% | 273 |
| 3 | Lighting & signalling | 1.5% | 198 |
| 4 | Brakes | 1.4% | 181 |
| 5 | Emissions & environmental | 0.4% | 45 |
| 6 | Steering | 0.3% | 41 |
Most common specific failures
The exact components most often recorded as failures — more specific than the categories above.
| # | Failure item | Times recorded |
|---|---|---|
| 1 | Wipers | 446 |
| 2 | Brake pads | 181 |
| 3 | Headlamp aim | 136 |
| 4 | Washers | 112 |
| 5 | Tread depth | 103 |
| 6 | Track rod end | 50 |
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 | 13.8% | 1,781 |
| 2 | Brakes | 9.8% | 1,267 |
| 3 | Other defects | 5.7% | 736 |
| 4 | Visibility | 3.0% | 387 |
| 5 | Steering | 1.9% | 244 |
| 6 | Emissions & environmental | 0.5% | 67 |
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 | 9,234 | 4.5% |
| 30-60k | 3,450 | 9.8% |
| 60-90k | 190 | 13.2% |
Failure rate by age
By fuel type
| Fuel | Tests | Fail rate |
|---|---|---|
| Hybrid | 7,702 | 5.3% |
| Petrol | 5,184 | 7.2% |
Trend over time
| Dataset year | Tests | Fail rate |
|---|---|---|
| 2023 | 139 | 3.6% |
| 2024 | 6,278 | 5.3% |
| 2025 | 6,472 | 6.8% |
What to check before buying a 2021 Stonic
The failure pattern for this year is specific enough to inspect against: visibility accounted for 3.8% of tests. Start there.
- Visibility (3.8% of tests): Wipers, washers, mirrors and screen damage — usually inexpensive, but check for chips in the driver's line of sight. Typical repair: £15–£150.
- Tyres (2.1% 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.
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 Kia Stonics pass their MOT?
94.0% of the 12,889 2021 Kia Stonic MOT tests in this dataset passed — a 6.0% fail rate.
What is the most common MOT failure on a 2021 Kia Stonic?
Visibility, recorded in 3.8% of tests, followed by tyres (2.1%).
Does the 2021 Stonic get worse with mileage?
Its MOT fail rate rises from 4.5% in the 0-30k band to 13.2% in the 60-90k band.
Methodology & source. Based on 12,889 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.