MERCEDES GLC (2021)
Running costs, common problems, and reliability data based on 6,414 real MOT tests in 2024.
MOT Pass Rate
95%
Total Tests (2024)
6,414
Avg Mileage
29,460 mi
Est. Annual Cost
£2,037
Is the 2021 MERCEDES GLC reliable?
Excellent reliability. Very few MOT failures. That's 13 points above the national average of 82%. It also outperforms the MERCEDES brand average of 87%.
At 3 years old, 95% of MERCEDES GLCs from 2021 passed their MOT first time in 2024. That's based on 6,414 tests across the UK. The average mileage at this age is 29,460 miles.
How does the 2021 MERCEDES GLC compare?
Mileage Analysis
The average 2021 MERCEDES GLC has 29,460 miles on the clock, which is above the expected 22,200 miles for a 3-year-old car. Higher-mileage cars often have more motorway miles, which is generally less harmful than stop-start urban driving.
Best year to buy a MERCEDES GLC?
The most reliable year is the 2022 model with a 96% MOT pass rate, while the 2015 model has the lowest at 89%. The 2021 sits between the two at 95%.
How much does a 2021 MERCEDES GLC 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 GLC by Year
Checking a specific MERCEDES GLC?
Enter the reg plate to see its individual MOT history, mileage verification, and predicted costs.
About the 2021 MERCEDES GLC
The 2021 MERCEDES GLC is a large car with a 2996cc petrol engine. 6,414 of these vehicles were MOT tested in 2024, making it a reasonably common sight on UK roads. It ranks in the top 22% of all 2021 cars for reliability.
With an average of 29,460 miles at 3 years old, MERCEDES GLC owners cover more miles than the average driver.
2021 MERCEDES GLC Fuel Costs
The 2996cc petrol engine is on the larger side, so fuel won't be this car's strong point. Expect around 30 mpg in mixed driving, which works out to roughly £1,592 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 GLC?
Total estimated annual running cost is £2,037 (£170/month), broken down as £1592 fuel, £190 road tax, £55 MOT, and £200 predicted repairs. The low repair estimate reflects the excellent 95% pass rate. These cars rarely fail their MOT, so unexpected bills are less likely.
MERCEDES GLC Reliability Trend
Newer MERCEDES GLCs show better MOT pass rates than older ones, with an average improvement of 5 percentage points.
Buying a Used 2021 MERCEDES GLC
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 2022 model has the highest pass rate at 96%. With 6,414 MOT tests in our data, there's strong statistical confidence in these figures.
Alternatives to the 2021 MERCEDES GLC
The MERCEDES GLC is actually the most reliable option among similar petrol large cars from this era. Here are comparable petrol cars with similar engines:
- BMW 5 SERIES (2019) 92% pass rate (-3%) from 33,766 tests
- BMW X3 (2019) 92% pass rate (-3%) from 32,937 tests
- BMW X5 (2019) 92% pass rate (-3%) from 23,506 tests
- AUDI Q5 (2020) 95% pass rate (same) from 16,809 tests