MERCEDES CLA (2021)
Running costs, reliability data, and common problems from 12,888 real MOT tests.
Annual Cost
£1,587
£132/month
MOT Pass Rate
92%
Excellent
Road Tax
£195
Flat rate/year
Insurance
Grp 8-20
1332cc Petrol
Great Choice
92% pass rate, £1587/year to run. 10 points above average.
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Annual Running Costs
~42 mpg
Flat rate (post-2017)
Low estimate due to excellent reliability
Based on 7,400 miles/year (UK average), current fuel prices, and repair likelihood from MOT data. Insurance not included.
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Reliability Verdict
Excellent reliability. Very few MOT failures. That's 10 points above the national average of 82%. It also outperforms the MERCEDES brand average of 87%.
At 5 years old, 92% of MERCEDES CLAs from 2021 passed their MOT first time in 2026. That's based on 12,888 tests across the UK. The average mileage at this age is 28,983 miles.
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How Does It Compare?
Mileage Analysis
28,983
Average miles
37,000
Expected for age
The average 2021 MERCEDES CLA has 28,983 miles on the clock, which is below the expected 37,000 miles for a 5-year-old car. This suggests lighter use than average, which generally means less wear on major components.
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Best Year to Buy?
The most reliable year is the 2022 model with a 96% MOT pass rate, while the 2013 model has the lowest at 84%. The 2021 sits between the two at 92%.
MERCEDES CLA by Year
Similar Cars to Consider
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About the 2021 MERCEDES CLA
The 2021 MERCEDES CLA is a small family car with a 1332cc petrol engine. 12,888 of these vehicles were MOT tested in 2026, making it one of the most commonly tested cars on UK roads. Among all cars from 2021, the average MOT pass rate is 92%, and this model falls short of that benchmark.
With an average of 28,983 miles at 5 years old, MERCEDES CLA owners tend to use this car less than the typical driver.
2021 MERCEDES CLA Fuel Costs
The 1332cc petrol engine offers a reasonable balance between performance and economy. Expect around 42 mpg in mixed driving, which works out to roughly £1,137 per year at current petrol prices of 142p per litre (based on 7,400 miles per year).
What does it cost to own a 2021 MERCEDES CLA?
Total estimated annual running cost is £1,587 (£132/month), broken down as £1137 fuel, £195 road tax, £55 MOT, and £200 predicted repairs. The low repair estimate reflects the excellent 92% pass rate. These cars rarely fail their MOT, so unexpected bills are less likely.
MERCEDES CLA Reliability Trend
Newer MERCEDES CLAs show better MOT pass rates than older ones, with an average improvement of 6 percentage points.
Buying a Used 2021 MERCEDES CLA
At 5 years old, the MERCEDES CLA offers good value with plenty of life remaining. Most manufacturer warranties will have expired, so a pre-purchase inspection is worth the cost. If you're flexible on year, the 2022 model has the highest pass rate at 96%. With 12,888 MOT tests in our data, there's strong statistical confidence in these figures.
Common Issues to Watch For
Based on the 2021 MERCEDES CLA's fuel type, age, and engine size, these are the most likely problem areas to check.
Service History
Low riskAlways request a full service history. Regular servicing is the single best indicator of how well a car has been maintained, regardless of mileage.
Running Costs Compared
How the 2021 MERCEDES CLA stacks up against similar cars for annual running costs, insurance, and tax.
| Car | Pass Rate | Fuel/yr | Tax/yr | Insurance | Total/yr |
|---|---|---|---|---|---|
| MERCEDES CLA(2021) | 92% | £1137 | £195 | Grp 8-20 | £1587 |
| FORD FIESTA(2019) | 91% | £955 | £190 | Grp 1-8 | £1400-£187 |
| VOLKSWAGEN GOLF(2019) | 92% | £1137 | £190 | Grp 12-25 | £1582-£5 |
| VAUXHALL CORSA(2019) | 88% | £1137 | £190 | Grp 8-20 | £1732+£145 |
| NISSAN QASHQAI(2020) | 93% | £1137 | £190 | Grp 12-25 | £1582-£5 |
Estimates based on 7,400 miles/year, current fuel prices, and MOT data. Insurance groups are indicative. Actual costs vary by driver, location, and usage.
Related Mercedes Models
Explore other Mercedes cars or similar models in the same category.
MERCEDES A
2019 · 1461cc Diesel
MERCEDES C
2017 · 1991cc Hybrid
MERCEDES A-CLASS
2017 · 1461cc Diesel
FORD FIESTA
2019 · 998cc Petrol
VOLKSWAGEN GOLF
2019 · 1498cc Petrol
VAUXHALL CORSA
2019 · 1398cc Petrol
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