MERCEDES S 500 L AMG LINE PRM+MHEV 4M A (2021)
Running costs, common problems, and reliability data based on 46 real MOT tests in 2024.
MOT Pass Rate
96%
Total Tests (2024)
46
Avg Mileage
30,040 mi
Est. Annual Cost
£2,037
Is the 2021 MERCEDES S 500 L AMG LINE PRM+MHEV 4M A reliable?
Excellent reliability. Very few MOT failures. That's 14 points above the national average of 82%. It also outperforms the MERCEDES brand average of 87%.
At 3 years old, 96% of MERCEDES S 500 L AMG LINE PRM+MHEV 4M As from 2021 passed their MOT first time in 2024. That's based on 46 tests across the UK. The average mileage at this age is 30,040 miles.
How does the 2021 MERCEDES S 500 L AMG LINE PRM+MHEV 4M A compare?
Mileage Analysis
The average 2021 MERCEDES S 500 L AMG LINE PRM+MHEV 4M A has 30,040 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.
How much does a 2021 MERCEDES S 500 L AMG LINE PRM+MHEV 4M A 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.
Checking a specific MERCEDES S 500 L AMG LINE PRM+MHEV 4M A?
Enter the reg plate to see its individual MOT history, mileage verification, and predicted costs.
About the 2021 MERCEDES S 500 L AMG LINE PRM+MHEV 4M A
The 2021 MERCEDES S 500 L AMG LINE PRM+MHEV 4M A is a large car with a 2999cc hybrid engine. 46 of these vehicles were MOT tested in 2024, making it a rare model on UK roads. It ranks in the top 21% of all 2021 cars for reliability.
With an average of 30,040 miles at 3 years old, MERCEDES S 500 L AMG LINE PRM+MHEV 4M A owners cover more miles than the average driver.
2021 MERCEDES S 500 L AMG LINE PRM+MHEV 4M A Fuel Costs
The 2999cc hybrid 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 hybrid prices of 142p per litre (based on 7,400 miles per year). As a hybrid, real-world fuel costs will vary significantly depending on how much electric-only driving you do.
What does it cost to own a 2021 MERCEDES S 500 L AMG LINE PRM+MHEV 4M A?
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 96% pass rate. These cars rarely fail their MOT, so unexpected bills are less likely.
Buying a Used 2021 MERCEDES S 500 L AMG LINE PRM+MHEV 4M A
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. Note: with only 46 tests in our data, these figures should be treated as indicative rather than definitive.
Alternatives to the 2021 MERCEDES S 500 L AMG LINE PRM+MHEV 4M A
The MERCEDES S 500 L AMG LINE PRM+MHEV 4M A is actually the most reliable option among similar hybrid large cars from this era. Here are comparable hybrid cars with similar engines:
- TOYOTA RAV4 (2020) 95% pass rate (-1%) from 21,063 tests
- BMW X5 XDRIVE45E M SPORT AUTO (2021) 88% pass rate (-8%) from 7,560 tests
- BMW M340I XDRIVE MHEV AUTO (2021) 93% pass rate (-3%) from 4,809 tests
- LEXUS RX (2019) 96% pass rate (same) from 4,047 tests