2018 BMW 420 MOT pass rate: 87.4% (30,456 tests)
Is the 2018 420 getting worse?
Pass rate of 2018-registered cars across recent test years:
| Test year | Pass rate | |
|---|---|---|
| 2023 | 88.1% +0.1 vs same-age |
|
| 2024 | 87.2% +1.0 vs same-age |
|
| 2025 | 86.8% +2.0 vs same-age |
The raw rate normally falls as cars age. The “vs same-age” figure compares this cohort with all UK cars registered in the same year, so normal ageing is not mistaken for a bad model year.
What fails on a 2018 420
| # | System | Defects recorded | Share |
|---|---|---|---|
| 1 | Tyres | 3,223 | 53.7% |
| 2 | Brakes | 903 | 15.1% |
| 3 | Lamps, reflectors and electrical equipment | 457 | 7.6% |
| 4 | Visibility | 403 | 6.7% |
| 5 | Road Wheels | 303 | 5.1% |
| 6 | Suspension | 276 | 4.6% |
All 420 years compared
| Registration year | Tests | Pass rate | Vs same-age | Median mileage |
|---|---|---|---|---|
| 2013 | 1,650 | 79.5% | +6.2 pts | 95,744 |
| 2014 | 22,950 | 80.3% | +4.5 pts | 85,570 |
| 2015 | 30,312 | 83.3% | +4.6 pts | 79,202 |
| 2016 | 33,734 | 85.6% | +4.2 pts | 71,172 |
| 2017 | 33,477 | 86.7% | +2.7 pts | 60,278 |
| 2018 (this page) | 30,456 | 87.4% | +1.0 pts | 47,658 |
| 2019 | 22,641 | 87.3% | -1.1 pts | 39,105 |
| 2020 | 9,404 | 89.3% | -0.6 pts | 29,748 |
Weighing up which year to buy? See the full ranking: BMW 420 years to avoid.
- Free MOT history checkThe exact car’s failures, advisories and mileage trail — sellers can’t edit it
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- XTOOL diagnostic toolsXTOOL code readers for petrol and diesel cars
- Autel UK testersAutel professional-grade diagnostic testers
FAQs
Is a 2018 BMW 420 reliable?
2018-registered examples passed 87.4% of their MOT tests (30,456 tests, 2023–2025), +1.0 points versus all UK cars registered in the same year. At roughly 8 years old with a median 47,658 miles, condition now varies car by car — always check the individual MOT history.
What mileage is too high for a 2018 420?
The median tested example shows 47,658 miles. Anything far beyond that isn't automatically bad — a motorway-mile car with consistent service records often beats a low-mileage school-run car — but price accordingly and scrutinise the mileage trail for gaps or drops.
Source: DVSA Anonymised MOT tests and results, 2023–2025 extracts (96 million Class 4 initial tests; retests excluded). Only vehicles old enough for a routine first MOT are included. Age-adjusted figures compare the model-year cohort with all vehicles of the same registration year tested in the same calendar year. Contains public sector information licensed under OGL v3.0.