2018 Kia Rio — MOT failures & pass rate
31,225 MOT tests on the 2018 Kia Rio are in this dataset, and 91.3% of them passed. Superminis of a similar age fail 11.2% of the time, so this is 2.5pp 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 (4.3%) and tyres (3.9%) are close, so failures are spread across several systems rather than one weak point.
At component level the recurring items are wipers, tread depth and brake pads — wipers alone was recorded 1,225 times.
A 120-150k example is materially riskier than a 0-30k one: 18.3% versus 5.9%.
The petrol cars hold up better: 8.6% fail against 10.9% for diesel, a 2.4-point gap across 31,225 tests.
Tyres is the most common advisory, noted on 22.4% of tests — work that passed today but is likely due soon.
The trend is worsening — 4.9% of tests failed in 2021 against 10.5% in 2025, the usual pattern as a fleet ages.
How it compares
Top failure categories
| # | Category | % of tests affected | Tests |
|---|---|---|---|
| 1 | Visibility | 4.3% | 1,340 |
| 2 | Tyres | 3.9% | 1,218 |
| 3 | Lighting & signalling | 2.5% | 793 |
| 4 | Brakes | 1.9% | 603 |
| 5 | Suspension | 0.7% | 216 |
| 6 | Emissions & environmental | 0.3% | 102 |
Most common specific failures
The exact components most often recorded as failures — more specific than the categories above.
| # | Failure item | Times recorded |
|---|---|---|
| 1 | Wipers | 1,225 |
| 2 | Tread depth | 614 |
| 3 | Brake pads | 544 |
| 4 | Washers | 393 |
| 5 | Headlamp aim | 383 |
| 6 | Headlamp | 277 |
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 | 22.4% | 7,009 |
| 2 | Brakes | 11.0% | 3,428 |
| 3 | Other defects | 7.2% | 2,242 |
| 4 | Visibility | 3.2% | 989 |
| 5 | Suspension | 1.0% | 322 |
| 6 | Steering | 1.0% | 302 |
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 | 15,650 | 5.9% |
| 30-60k | 12,565 | 10.6% |
| 60-90k | 2,561 | 14.7% |
| 90-120k | 363 | 15.2% |
| 120-150k | 60 | 18.3% |
Failure rate by age
By fuel type
| Fuel | Tests | Fail rate |
|---|---|---|
| Petrol | 29,863 | 8.6% |
| Diesel | 1,362 | 10.9% |
Trend over time
| Dataset year | Tests | Fail rate |
|---|---|---|
| 2021 | 6,076 | 4.9% |
| 2022 | 6,227 | 7.7% |
| 2023 | 6,341 | 9.6% |
| 2024 | 6,271 | 10.6% |
| 2025 | 6,310 | 10.5% |
What to check before buying a 2018 Rio
The failure pattern for this year is specific enough to inspect against: visibility accounted for 4.3% of tests. Start there.
- Visibility (4.3% 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 (3.9% 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 (2.5% 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 2018 Kia Rios pass their MOT?
91.3% of the 31,225 2018 Kia Rio MOT tests in this dataset passed — a 8.7% fail rate.
What is the most common MOT failure on a 2018 Kia Rio?
Visibility, recorded in 4.3% of tests, followed by tyres (3.9%).
Does the 2018 Rio get worse with mileage?
Its MOT fail rate rises from 5.9% in the 0-30k band to 18.3% in the 120-150k band.
Methodology & source. Based on 31,225 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.