In 2025, 22,037 Mercedes-Benz Cls cars had a regular MOT in Great Britain. 74% passed first time, compared with 68% for all cars of the same ages, which makes the Cls better than average. Adjusted for age, it ranks 25 of the 217 most-tested car models.
That comparison matters: older cars fail more often, so a raw pass rate flatters models that are mostly young. We compare each model against every car on the road at the same age.
Pass rate by age
At 5 years old, 81% of Clss passed first time (all cars that age: 86%). By 20 years, that figure is 71% (all cars: 58%). It is weaker than average when young but holds up better than most from around 9 years.
Mercedes-Benz Cls All cars of that age
| Age | Tests | Cls passed first time | All cars | Typical mileage |
|---|---|---|---|---|
| 5 years | 274 | 81% | 86% | 43,229 |
| 6 years | 1,071 | 83% | 84% | 51,145 |
| 7 years | 947 | 82% | 81% | 58,029 |
| 8 years | 1,463 | 80% | 78% | 68,225 |
| 9 years | 2,085 | 80% | 75% | 78,273 |
| 10 years | 2,853 | 79% | 72% | 88,772 |
| 11 years | 1,727 | 75% | 69% | 93,448 |
| 12 years | 2,960 | 72% | 66% | 103,473 |
| 13 years | 1,058 | 74% | 63% | 103,049 |
| 14 years | 1,092 | 74% | 61% | 106,387 |
| 15 years | 974 | 66% | 59% | 116,021 |
| 16 years | 942 | 66% | 58% | 116,875 |
| 17 years | 1,156 | 69% | 57% | 123,778 |
| 18 years | 1,427 | 68% | 57% | 124,857 |
| 19 years | 1,126 | 70% | 57% | 118,957 |
| 20 years | 820 | 71% | 58% | 107,351 |
What fails most on a Mercedes-Benz Cls
The area that lets the Cls down most, relative to other cars, is road wheels: 2.2% of tests failed on it, 17.9 times the rate for the average car. It does comparatively well on visibility and lights and electrics.
Share of Cls tests failing on this area Average car
The six most common failure items
| Failure item | Area | Share of tests |
|---|---|---|
| A tyre seriously damaged | Tyres | 4.8% |
| A spring or spring component fractured or seriously weakened | Suspension | 4.1% |
| Tyre tread depth not in accordance with the requirements | Tyres | 3.9% |
| A tyre cords visible or damaged | Tyres | 3.9% |
| A suspension pin, bush or joint excessively worn | Suspension | 3.7% |
| Brake pipe damaged or excessively corroded | Brakes | 3.1% |
What to check when buying a used Cls
Based on where the Cls fails more often than other cars, these are the checks worth making before you buy:
- Road wheels: Look for damaged rims and missing wheel nuts. More
- Tyres: Check tread across the whole width (uneven wear hints at alignment or suspension faults), and look for cuts, bulges and mismatched brands. Repair guide
- Brakes: Look through the wheels for lipped or scored discs, check the handbrake holds on a slope, and feel for pulling or vibration under firm braking. Repair guide
Then check the individual car: its own MOT history will show whether it follows the pattern. A car with repeated advisories in the same weak area is more likely to fail its next test.
Check a specific Cls
Enter the registration to see its full MOT history, mileage record and reliability score, compared with these figures.
Check a ClsFrequently asked questions
What is the MOT pass rate for a Mercedes-Benz Cls?
In 2025, 74% of Mercedes-Benz Cls cars passed their MOT first time, across 22,037 tests. Cars of the same ages averaged 68%.
What do Mercedes-Benz Cls cars most often fail their MOT on?
The most common failure items were: a tyre seriously damaged (4.8% of tests); a spring or spring component fractured or seriously weakened (4.1% of tests); tyre tread depth not in accordance with the requirements (3.9% of tests).
Other Mercedes-Benz models
Mercedes-Benz C-Class (74%), Mercedes-Benz A-Class (77%), Mercedes-Benz E-Class (77%), Mercedes-Benz Vito (67%), Mercedes-Benz B-Class (72%), Mercedes-Benz Glc (85%). All Mercedes-Benz models
Source: DVSA anonymised MOT tests and results, 2025 (class 4 normal tests; first-time pass means passed with no faults fixed at the test). Contains public sector information licensed under the Open Government Licence v3.0.