MERCEDES S 350 AMG LINE PREMIUM D AUTO (2021)
Running costs, common problems, and reliability data based on 33 real MOT tests in 2024.
MOT Pass Rate
100%
Total Tests (2024)
33
Avg Mileage
42,099 mi
Est. Annual Cost
£1,690
Is the 2021 MERCEDES S 350 AMG LINE PREMIUM D AUTO reliable?
Excellent reliability. Very few MOT failures. That's 18 points above the national average of 82%. It also outperforms the MERCEDES brand average of 87%.
At 3 years old, 100% of MERCEDES S 350 AMG LINE PREMIUM D AUTOs from 2021 passed their MOT first time in 2024. That's based on 33 tests across the UK. The average mileage at this age is 42,099 miles.
How does the 2021 MERCEDES S 350 AMG LINE PREMIUM D AUTO compare?
Mileage Analysis
The average 2021 MERCEDES S 350 AMG LINE PREMIUM D AUTO has 42,099 miles on the clock, which is well above the expected 22,200 miles for a 3-year-old car. Check service history carefully, as high-mileage cars need consistent maintenance to stay reliable.
How much does a 2021 MERCEDES S 350 AMG LINE PREMIUM D AUTO 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 350 AMG LINE PREMIUM D AUTO?
Enter the reg plate to see its individual MOT history, mileage verification, and predicted costs.
About the 2021 MERCEDES S 350 AMG LINE PREMIUM D AUTO
The 2021 MERCEDES S 350 AMG LINE PREMIUM D AUTO is a large car with a 2925cc diesel engine. 33 of these vehicles were MOT tested in 2024, making it a rare model on UK roads. It ranks in the top 3% of all 2021 cars for reliability.
With an average of 42,099 miles at 3 years old, MERCEDES S 350 AMG LINE PREMIUM D AUTO owners cover more miles than the average driver. High-mileage examples should be checked carefully for wear on suspension, brakes, and drivetrain components.
2021 MERCEDES S 350 AMG LINE PREMIUM D AUTO 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 S 350 AMG LINE PREMIUM D AUTO?
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 100% pass rate. These cars rarely fail their MOT, so unexpected bills are less likely.
Buying a Used 2021 MERCEDES S 350 AMG LINE PREMIUM D AUTO
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 33 tests in our data, these figures should be treated as indicative rather than definitive.
Alternatives to the 2021 MERCEDES S 350 AMG LINE PREMIUM D AUTO
The MERCEDES S 350 AMG LINE PREMIUM D AUTO is actually the most reliable option among similar diesel large cars from this era. Here are comparable diesel cars with similar engines:
- MERCEDES E (2019) 90% pass rate (-10%) from 41,000 tests
- FORD RANGER (2019) 87% pass rate (-13%) from 32,194 tests
- AUDI Q5 (2019) 93% pass rate (-7%) from 24,241 tests
- AUDI A5 (2019) 90% pass rate (-10%) from 22,290 tests