BMW 420

Reliability, estimated running costs, and MOT data across 9 model years from 141,320 MOT tests in 2024.

Avg Pass Rate

89%

Total Tests

141,320

Highest Pass Rate

2021 (94%)

Years Covered

About the BMW 420

The BMW 420 was MOT tested 141,320 times in 2024 (DVSA data, retests included) across 9 model years (2013 to 2021), with an average pass rate of 89%. That's comfortably above the average of 82% across all models in our data. Our records list diesel and petrol versions.

Best and Worst Years

Of the years with at least 100 tests, the 2021 model has the highest pass rate at 94% from 730 tests. The 2013 model has the lowest at 85%. The 9 point gap means pass rates vary somewhat between years, but no year is dramatically different. Newer cars usually pass more often simply because they are younger.

Reliability Trend

Newer BMW 420s pass their MOT more often than older ones, by 4 percentage points on average, which is mostly down to age and wear.

Mileage Across Years

The oldest model in our data (2013) averages 99,720 miles, while the newest (2021) averages 28,172 miles.

Estimated Running Costs

Fuel (Diesel, 1995cc)

£1,397

Road Tax

£200

MOT Test

£55

Predicted Repairs

£200

Total per year£1,852

Per month£154/mo

Based on 7,400 miles/year, average pump prices of 174.57p petrol and 199.33p diesel (GOV.UK weekly road fuel prices, week of 19 October 2026), and MOT pass rate data. Insurance not included.

Full 2021 details

How reliable is the BMW 420?

vs average of all models+7% (82% avg)

vs BMW brand average+1% (88% avg)

Best to worst year spread9 percentage points

Reliability trendImproving over years

BMW 420 by Year

Click any year to see detailed running costs, reliability data, and comparisons with similar cars.

Year	Pass Rate	Tests	Avg Mileage
2021	94%	730	28,172 mi
2020	92%	6,832	32,973 mi
2019	90%	16,835	41,885 mi
2018	91%	22,374	51,167 mi
2017	90%	25,467	64,302 mi
2016	89%	25,224	75,338 mi
2015	88%	23,559	82,955 mi
2014	86%	18,990	89,334 mi
2013	85%	1,309	99,720 mi

Questions about the BMW 420

Is the BMW 420 reliable?

Across its 9 model years in our data (2013 to 2021), the BMW 420 averages an 89% MOT pass rate, from 141,320 tests (DVSA MOT data for tests in 2024, retests included). That's 7 points above the average of 82% across all models in the same data. The 2021 model has the highest pass rate of the years with at least 100 tests, at 94%.

Which year BMW 420 has the best MOT pass rate?

Of the years with at least 100 tests, the 2021 BMW 420 has the highest MOT pass rate at 94%, while the 2013 model has the lowest at 85%, a 9 point gap. Newer cars usually pass more often simply because they are younger, so compare years of a similar age.