MERCEDES CLS (2021)
Running costs, common problems, and reliability data based on 149 real MOT tests in 2024.
MOT Pass Rate
90%
Total Tests (2024)
149
Avg Mileage
25,838 mi
Est. Annual Cost
£1,690
Is the 2021 MERCEDES CLS reliable?
Excellent reliability. Very few MOT failures. That's 8 points above the national average of 82%.
At 3 years old, 90% of MERCEDES CLSs from 2021 passed their MOT first time in 2024. That's based on 149 tests across the UK. The average mileage at this age is 25,838 miles.
How does the 2021 MERCEDES CLS compare?
Mileage Analysis
The average 2021 MERCEDES CLS has 25,838 miles on the clock, which is in line with the expected 22,200 miles for a 3-year-old car, suggesting normal everyday use.
Best year to buy a MERCEDES CLS?
The most reliable year is the 2019 model with a 90% MOT pass rate, while the 2009 model has the lowest at 78%. The 2021 sits between the two at 90%.
How much does a 2021 MERCEDES CLS cost to run?
Based on 7,400 miles/year (UK average), current fuel prices, and repair likelihood from MOT pass rate data. Insurance not included.
MERCEDES CLS by Year
| Year | Pass Rate | Tests | Avg Mileage |
|---|---|---|---|
| 2021 | 90% | 149 | 25,838 mi |
| 2020 | 85% | 708 | 33,613 mi |
| 2019 | 90% | 2,938 | 42,687 mi |
| 2018 | 89% | 2,552 | 49,336 mi |
| 2017 | 87% | 3,475 | 61,581 mi |
| 2016 | 87% | 4,786 | 69,870 mi |
| 2015 | 87% | 6,871 | 81,130 mi |
| 2014 | 85% | 4,192 | 86,883 mi |
| 2013 | 83% | 7,096 | 95,825 mi |
| 2012 | 83% | 2,664 | 97,844 mi |
| 2011 | 82% | 2,675 | 100,976 mi |
| 2010 | 79% | 2,428 | 110,846 mi |
| 2009 | 78% | 2,541 | 114,393 mi |
| 2008 | 78% | 2,982 | 122,863 mi |
| 2007 | 78% | 3,915 | 122,774 mi |
| 2006 | 79% | 3,184 | 117,836 mi |
| 2005 | 81% | 1,944 | 108,622 mi |
Checking a specific MERCEDES CLS?
Enter the reg plate to see its individual MOT history, mileage verification, and predicted costs.
About the 2021 MERCEDES CLS
The 2021 MERCEDES CLS is a large car with a 2925cc diesel engine. 149 of these vehicles were MOT tested in 2024, making it a rare model on UK roads. It sits in the bottom 76% of 2021 cars for MOT pass rates.
With an average of 25,838 miles at 3 years old, MERCEDES CLS owners drive about as much as the UK average.
2021 MERCEDES CLS Fuel Costs
The 2925cc diesel engine is on the larger side, so fuel won't be this car's strong point. Expect around 40 mpg in mixed driving, which works out to roughly £1,245 per year at current diesel prices of 148p per litre (based on 7,400 miles per year).
What does it cost to own a 2021 MERCEDES CLS?
Total estimated annual running cost is £1,690 (£141/month), broken down as £1245 fuel, £190 road tax, £55 MOT, and £200 predicted repairs. The low repair estimate reflects the excellent 90% pass rate. These cars rarely fail their MOT, so unexpected bills are less likely.
MERCEDES CLS Reliability Trend
Newer MERCEDES CLSs show better MOT pass rates than older ones, with an average improvement of 7 percentage points.
Buying a Used 2021 MERCEDES CLS
At 3 years old, this is still relatively fresh. You may find examples with remaining manufacturer warranty. Depreciation is slowing but hasn't bottomed out yet. If you're flexible on year, the 2019 model has the highest pass rate at 90%.
Alternatives to the 2021 MERCEDES CLS
If reliability is your priority, there's one similar car with a higher MOT pass rate. Here are comparable diesel cars with similar engines:
- MERCEDES E (2019) 90% pass rate (same) from 41,000 tests
- FORD RANGER (2019) 87% pass rate (-3%) from 32,194 tests
- AUDI Q5 (2019) 93% pass rate (+3%) from 24,241 tests
- AUDI A5 (2019) 90% pass rate (same) from 22,290 tests