Mercedes-Benz B-Class: 70% pass.

60,740 tests of cars aged 3 and over passed first time 70% of the time in 2025. For cars of the same ages, 67% would be expected: 3 points better than that.

How it does as it ages.

01 / By age

Source: Anonymised MOT tests and results (Driver and Vehicle Standards Agency) Checked 4 Nov 2026, 13:37

Diesel
Age of car	Pass first time	All cars this age	Fixed at the station	Failed	Tests
5 years	84%	84%	1%	15%	80
6 years	83%	82%	2%	15%	1,208
7 years	80%	79%	3%	16%	3,250
8 years	80%	76%	3%	18%	4,687
9 years	76%	73%	5%	20%	4,257
10 years	72%	70%	5%	23%	5,834
11 years	71%	67%	5%	24%	6,839
12 years	68%	64%	5%	27%	4,566
13 years	64%	62%	6%	30%	2,381
14 years	57%	60%	7%	36%	2,000
15 years	56%	58%	6%	38%	2,005
16 years	56%	57%	5%	39%	1,678
17 years	56%	57%	7%	37%	1,321
18 years	52%	57%	8%	40%	799
19 years	53%	57%	6%	41%	373

Electric
Age of car	Pass first time	All cars this age	Fixed at the station	Failed	Tests
7 years	79%	79%	0%	21%	34
8 years	75%	76%	5%	19%	171
9 years	81%	73%	1%	18%	143
10 years	74%	70%	0%	26%	43

Petrol
Age of car	Pass first time	All cars this age	Fixed at the station	Failed	Tests
5 years	89%	84%	1%	9%	265
6 years	86%	82%	2%	11%	1,651
7 years	85%	79%	3%	13%	1,081
8 years	84%	76%	2%	13%	817
9 years	83%	73%	3%	14%	813
10 years	81%	70%	3%	16%	816
11 years	76%	67%	5%	19%	1,334
12 years	75%	64%	5%	20%	1,580
13 years	66%	62%	7%	27%	1,448
14 years	60%	60%	8%	32%	2,205
15 years	60%	58%	8%	32%	2,339
16 years	58%	57%	8%	33%	1,714
17 years	57%	57%	9%	34%	1,188
18 years	56%	57%	9%	35%	1,151
19 years	59%	57%	9%	32%	624
20 years	60%	57%	16%	24%	45

Ages with fewer than 30 tests are left out. "All cars this age" is every make and model at that age, so you can see whether this one does better or worse than most.

A pass rate is the share of normal MOT tests a car passed first time, with no repair needed at the test station. A car that failed and was fixed on the spot is counted separately. Retests, aborted tests and other vehicles are left out.
The figures say how often cars of a kind pass, not how reliable or safe they are. Cars that are looked after better, or that are driven fewer miles, pass more often, and that differs by model. Groups of fewer than 30 tests are left out.
Make and model names are as DVSA records them, and a model can appear under more than one name.

More on Mercedes-Benz and costs.

02 / Related

Data sources

Anonymised MOT tests and results (Driver and Vehicle Standards Agency). Contains public sector information licensed under the Open Government Licence v3.0. MOT test results for cars, counted by make, model and age from DVSA's anonymised data. The counts are ours; DVSA does not endorse them.