2021 Kia Rio — MOT failures & pass rate
The 2021 Kia Rio passed 92.8% of its 7,820 recorded MOT tests. That is effectively the same as superminis of a similar age (7.8% fail rate), so the MOT record here is unremarkable in either direction. Failures cluster in visibility, tyres and lighting & signalling.
What the MOT record shows
No single area dominates — visibility (3.9%) and tyres (3.1%) 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 290 times.
Mileage is the strongest signal on the record: 5.1% of 0-30k cars fail, rising to 20.3% once past 60-90k — 4.0× the risk.
Fuel type barely separates them — petrol fails 7.0% of the time against 7.7% for hybrid.
Tyres is the most common advisory, noted on 17.4% of tests — work that passed today but is likely due soon.
The trend is worsening — 2.9% of tests failed in 2023 against 8.9% in 2025, the usual pattern as a fleet ages.
How it compares
Top failure categories
| # | Category | % of tests affected | Tests |
|---|---|---|---|
| 1 | Visibility | 3.9% | 301 |
| 2 | Tyres | 3.1% | 246 |
| 3 | Lighting & signalling | 2.1% | 165 |
| 4 | Brakes | 1.3% | 104 |
| 5 | Steering | 0.4% | 33 |
| 6 | Emissions & environmental | 0.4% | 27 |
Most common specific failures
The exact components most often recorded as failures — more specific than the categories above.
| # | Failure item | Times recorded |
|---|---|---|
| 1 | Wipers | 290 |
| 2 | Brake pads | 105 |
| 3 | Headlamp aim | 71 |
| 4 | Washers | 66 |
| 5 | Headlamp | 63 |
| 6 | Tread depth | 62 |
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 | 17.4% | 1,358 |
| 2 | Brakes | 8.1% | 631 |
| 3 | Other defects | 5.6% | 435 |
| 4 | Visibility | 3.4% | 262 |
| 5 | Steering | 3.0% | 234 |
| 6 | Lighting & signalling | 0.5% | 42 |
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 | 5,488 | 5.1% |
| 30-60k | 2,077 | 11.3% |
| 60-90k | 232 | 20.3% |
Failure rate by age
By fuel type
| Fuel | Tests | Fail rate |
|---|---|---|
| Petrol | 5,189 | 7.0% |
| Hybrid | 2,631 | 7.7% |
Trend over time
| Dataset year | Tests | Fail rate |
|---|---|---|
| 2023 | 105 | 2.9% |
| 2024 | 3,745 | 5.5% |
| 2025 | 3,963 | 8.9% |
What to check before buying a 2021 Rio
The failure pattern for this year is specific enough to inspect against: visibility accounted for 3.9% of tests. Start there.
- Visibility (3.9% 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 (3.1% 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 (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 Kia Rios pass their MOT?
92.8% of the 7,820 2021 Kia Rio MOT tests in this dataset passed — a 7.2% fail rate.
What is the most common MOT failure on a 2021 Kia Rio?
Visibility, recorded in 3.9% of tests, followed by tyres (3.1%).
Does the 2021 Rio get worse with mileage?
Its MOT fail rate rises from 5.1% in the 0-30k band to 20.3% in the 60-90k band.
Methodology & source. Based on 7,820 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.