HowreliableUsed car reliability from every MOT

CarsMercedes C-Class

MOT results · tests in 2025 · Great Britain

Mercedes C-Class reliability: what the MOT shows

342,898 C-Classes had an MOT in 2025. 75.2% passed first time, against 69.7% for other cars of the same age and mileage. That is 5.5 points better than comparable cars. Those registered from 2020 onwards pass as often as other cars their age.

75.2%passed first time

+5.5points against cars of the same age and mileage

342,898MOTs in 2025

Report card

Mercedes C-Class MOT results by registration year

Each dot compares how often C-Classes of that year failed on one area of the test with cars of the same age and mileage.

Much betterBetterAbout the sameWorseMuch worse

Year	Passed first time	Against same age and mileage	MOTs
2005	59.7%	+3.2	7,263
2006	58.9%	+2.9	8,744
2007	61.7%	+5.2	11,387
2008	63.7%	+7.8	13,123
2009	64.4%	+7.9	12,581
2010	66.0%	+7.9	12,746
2011	67.5%	+7.6	18,748
2012	67.4%	+5.4	25,647
2013	69.8%	+5.5	23,428
2014	75.2%	+8.2	25,194
2015	78.0%	+8.0	34,050
2016	80.4%	+6.9	36,607
2017	81.6%	+4.2	39,536
2018	83.9%	+3.4	28,371
2019	85.6%	+2.3	24,651
2020	85.8%	+0.2	9,956
2021	87.2%	+0.3	6,195
2022	89.1%	+0.7	4,671

Much worse: failed on that area at least 1.5 times as often. Worse: 1.15 to 1.5 times. Better: up to 0.87 times. Much better: two-thirds as often or less. Gaps under half a percentage point count as about the same. Registration year is the year the car was first used.

Mercedes C-Class years to avoid, going by the MOT

Ahead2005 to 2019+2.3 to +8.2 ptsMost common failures: ball joint excessively worn in 2005, 2006, 2007, 2008, 2009, 2010, 2011, 2012 and 2013; tread depth below requirements of 1.6mm in 2014, 2015, 2016, 2017, 2018 and 2019. 322,076 MOTs.

Level2020 to 2022+0.2 to +0.7 ptsMost common failures: tread depth below requirements of 1.6mm in 2020 and 2021; condition (has a cut in excess of the requirements deep enough to reach the ply or cords) in 2022. 20,822 MOTs.

Well behind: 5 or more points below cars of the same age and mileage. Behind: 1.5 to 5 points below. Level: within 1.5 points. Ahead: 1.5 or more points above.

What fails

Mercedes C-Class common faults at the MOT

7.6% of C-Class MOTs failed on tyres, against 6.8% for cars of the same age and mileage, and 3.4% on emissions and leaks, against 3.5%.

Most common failures

Ball joint excessively worn4.2%Cars of the same age and mileage: 1.7%

Tread depth below requirements of 1.6mm3.1%Cars of the same age and mileage: 2.6%

Coil spring: fractured or broken2.6%Cars of the same age and mileage: 2.8%

Condition: has ply or cords exposed1.7%Cars of the same age and mileage: 1.5%

Condition: has a cut in excess of the requirements deep enough to reach the ply or cords1.5%Cars of the same age and mileage: 1.4%

Malfunction indicator lamp: inoperative or indicates a malfunction1.5%Cars of the same age and mileage: 1.0%

Linkage ball joint dust cover: ball joint dust cover no longer prevents the ingress of dirt1.3%Cars of the same age and mileage: 0.9%

Rbt (sp): efficiency below requirements1.3%Cars of the same age and mileage: 1.2%

C-ClassSame age and mileage

Fails more often than other cars

Condition: fractured6.2×0.37% of C-Class MOTs (1,264) against 0.06% for cars of the same age and mileage

Sub-frame: corroded and seriously weakened2.6×0.37% of C-Class MOTs (1,256) against 0.14% for cars of the same age and mileage

Ball joint excessively worn2.5×4.19% of C-Class MOTs (14,374) against 1.70% for cars of the same age and mileage

Rigid brake pipes: excessively corroded1.9×1.03% of C-Class MOTs (3,515) against 0.53% for cars of the same age and mileage

Malfunction indicator lamp: inoperative or indicates a malfunction1.7×1.22% of C-Class MOTs (4,183) against 0.73% for cars of the same age and mileage

Ball joint dust cover no longer prevents the ingress of dirt1.6×0.58% of C-Class MOTs (1,985) against 0.35% for cars of the same age and mileage

Mileage

Pulls ahead after 30,000 miles

Up to 30,000 miles, C-Classes pass as often as cars of the same age and mileage. Ahead from there: 30–60,000 miles 4.0 points, 60–90,000 miles 6.7 points, 90–120,000 miles 7.0 points, 120,000+ miles 5.1 points.

C-Class, first-time pass rateCars of the same age and mileage

Petrol, diesel or hybrid C-Class

Diesels passed 73.3% first time, 5.1 points above comparable cars; petrols passed 76.7%, 6.4 points above comparable cars. Diesels had a median of 92,216 miles at the test, against 67,295 for petrols.

Fuel	MOTs	Passed first time	Same age and mileage	Gap (pts)	Median miles
Diesel	210,256	73.3%	68.2%	+5.1	92,216
Petrol	107,624	76.7%	70.3%	+6.4	67,295
Hybrid	18,037	85.4%	80.6%	+4.8	53,388
Other	6,973	83.6%	78.7%	+4.9	64,969

Against rivals

C-Class against other executive cars

Cars registered 2014 to 2021, each against cars of the same age and mileage. The C-Class ranks 6 of 11.

Model	MOTs	Passed first time	Same age and mileage	Gap (pts)
1. BMW 5 Series	111,912	85.1%	75.4%	+9.7
2. BMW 3 Series	220,543	83.4%	76.2%	+7.2
3. VW Passat	86,106	79.6%	73.1%	+6.5
4. Jaguar XF	47,799	80.2%	74.1%	+6.1
5. Mercedes E-Class	140,596	81.9%	75.8%	+6.0
6. Mercedes C-Class	204,560	81.2%	76.0%	+5.2
7. Skoda Superb	49,005	80.1%	76.0%	+4.2
8. Jaguar XE	42,769	81.0%	77.2%	+3.8
9. Audi A4	117,487	79.1%	75.3%	+3.8
10. Tesla Model 3	67,557	84.1%	84.4%	−0.3
11. Vauxhall Insignia	110,320	70.7%	72.0%	−1.4

Check these before you buy a used C-Class

What testers most often noted as advisories on C-Classes in 2025: wear that passed but was close to failing. Figures in brackets are for cars of the same age and mileage.

Tread depth: worn close to legal limit/worn on edge18% (17%)
Brake discs: worn, pitted or scored, but not seriously weakened8% (10%)
Brake pads: wearing thin7% (8%)
Rigid brake pipes: corroded, covered in grease or other material7% (4%)
Ball joint: ball joint has slight play5% (2%)
Condition: slightly damaged/cracking or perishing5% (9%)
Engine oil leaks: leak, but not excessive4% (6%)
Pins and bushes: pin or bush worn but not resulting in excessive movement4% (6%)

Questions about C-Class reliability

Is the Mercedes C-Class reliable?

At the MOT, 75.2% of 342,898 C-Class MOTs in 2025 passed first time, against 69.7% for cars of the same age and mileage. 2005 to 2019: ahead (+2.3 to +8.2 points). 2020 to 2022: level (+0.2 to +0.7 points).

Which Mercedes C-Class years should I avoid?

None stand out: every registration year is within 1.5 points of cars of the same age and mileage, or ahead of them.

What is the most common MOT failure on a C-Class?

Ball joint excessively worn: 4.2% of C-Class MOTs, against 1.7% for cars of the same age and mileage.

Is a diesel or petrol C-Class more reliable?

Petrol C-Classes passed 76.7% first time and diesels 73.3%. Against cars of the same age and mileage, petrols were 6.4 points above and diesels 5.1 points above.

Is the C-Class more reliable than the BMW 3 Series?

For cars registered 2014 to 2021, the BMW 3 Series passed 83.4% first time, +7.2 points against comparable cars. The C-Class passed 81.2%, +5.2 points.

How we measure

Data. Every car MOT in Great Britain in 2025 (31,475,521 first tests on cars first used 2005 to 2022), from DVSA's anonymised MOT test data. Retests are left out.

Passed first time. A car passed if its first test that year ended in a pass. Cars that failed and were fixed within the hour count as fails, as DVSA counts them.

Same age and mileage. We group every car by the year it was first used and its mileage (under 30k, 30–60k, 60–90k, 90–120k, over 120k). The comparison figure is what those groups scored, weighted to match the C-Class's mix of ages and mileages.

Model. Every car DVSA records as a Mercedes C-Class: 191 recorded model names, from "C" to trims such as "C 200 AMG LINE PREMIUM MHEV A".

The full method, including how each report-card dot and year group is decided.