Mercedes-Benz S-Class reliability, MPG and running costs
Figures updated
The Mercedes-Benz S-Class is a luxury car. In 2024 MOT tests it scored 181 for reliability (100 is average), ranking 32 of 442, and 16.6% failed first time against a UK average of 28.5%. Its most common MOT failure is ball joint (2.9% of tests).
Ranked 32 of 442 cars in the 2024 MOT Reliability League
In 2024, 24,267 Mercedes-Benz S-Classes aged 3 to 20 had an MOT and 16.6% failed first time (UK average 28.5%). Taking age and mileage into account, the Mercedes-Benz S-Class is 45% less likely to fail than the average car of the same age and mileage. At the first MOT, at three years old, 6.3% failed (UK 12.7%).
First-time fail rate
16.6%
UK 28.5%
Fail rate at 3 years
6.3%
UK 12.7%
Average miles a year
10,200
Typical age at test: 9 years
Mercedes-Benz S-Class MOT failure rate by age
Most common Mercedes-Benz S-Class MOT faults
- Ball joint: ball joint excessively worn2.9% of tests
- Tread depth: tread depth below requirements of 1.6mm2.2% of tests
- Malfunction indicator lamp: inoperative or indicates a malfunction1.9% of tests
- Condition: has ply or cords exposed1.2% of tests
- Condition: has a cut in excess of the requirements deep enough to reach the ply or cords1.1% of tests
- Brake pads: less than 1.5 mm thick0.8% of tests
What the Mercedes-Benz S-Class fails on
| Area | Tests failing | vs similar cars |
|---|---|---|
| Tyres | 5.4% | ▼ 21% less often |
| Suspension | 4.4% | ▼ 53% less often |
| Brakes | 4.0% | ▼ 46% less often |
| Lights and electrics | 3.3% | ▼ 72% less often |
| Exhaust and emissions | 2.8% | ▼ 22% less often |
| Visibility | 2.1% | ▼ 57% less often |
| Wheels | 0.7% | ▲ 1.7× as often |
| Seat belts and airbags | 0.7% | ▼ 34% less often |
| Body and structure | 0.6% | ▼ 84% less often |
| Steering | 0.4% | ▼ 80% less often |
What MPG does the Mercedes-Benz S-Class do?
Official economy for the Mercedes-Benz S-Class ranges from 19 to 61.4mpg across the 272 versions listed by the Vehicle Certification Agency (2004–2025). A typical petrol version manages 27.4mpg and a typical diesel 45.6mpg. Expect 10–15% less in real-world driving.
Work out a journey's fuel costHow much is road tax on a Mercedes-Benz S-Class?
Any Mercedes-Benz S-Class first registered from April 2017 pays the standard rate of £200 a year after its first year (2026/27 rates). A Mercedes-Benz S-Class registered between March 2001 and March 2017 is taxed on its CO2: £200 to £790 a year.
Work out tax for a specific carMercedes-Benz S-Class specs and running costs
Official figures for 272 versions sold in the UK between 2004 and 2025.
Fuel types
Diesel, Hybrid, Petrol, Plug-in hybrid
Official economy
19.0–61.4 mpg
CO2
13–357 g/km
Power
230–802 PS
| Version | Fuel | Economy | CO2 | Car tax | Company car tax |
|---|---|---|---|---|---|
| S-Class Saloon S 350 d L Saloon313 PS · A9 · listed 2025 | Diesel | 47.9 mpg | 155g | £200 | 37% |
| S-Class Saloon S 350 d Saloon313 PS · A9 · listed 2025 | Diesel | 47.9 mpg | 154g | £200 | 37% |
| S-Class Saloon S 450 d L 4MATIC Saloon367 PS · A9 · listed 2025 | Diesel | 45.6 mpg | 163g | £200 | 37% |
| S-Class Saloon S 500 4MATIC Saloon449 PS · A9 · listed 2025 | Petrol | 34.5 mpg | 186g | £200 | 37% |
| S-Class Saloon S 500 L 4MATIC Saloon449 PS · A9 · listed 2025 | Petrol | 34.5 mpg | 187g | £200 | 37% |
| S-Class Saloon Maybach S 580503 PS · A9 · listed 2025 | Petrol | 27.4 mpg | 233g | £200 | 37% |
| S-Class Saloon Maybach S 680612 PS · A9 · listed 2025 | Petrol | 21.4 mpg | 300g | £200 | 37% |
| S-Class Saloon S 450 e L Saloon408 PS · A9 · listed 2025 | Plug-in hybrid | 122.8 mpg | 52g | £200 | 17% |
| S-Class Saloon Maybach S 580 e510 PS · A9 · listed 2025 | Plug-in hybrid | 97.4 mpg | 66g | £200 | 20% |
| S-Class Saloon S 580 e L 4MATIC Saloon510 PS · A9 · listed 2025 | Plug-in hybrid | 108.7 mpg | 59g | £200 | 18% |
| S-Class Saloon AMG S 63 E Performance802 PS · A9 · listed 2025 | Plug-in hybrid | 35.8 mpg | 179g | £200 | 37% |
| S-Class Saloon S 350 d230 PS · A9 · listed 2024 | Diesel | 47.9 mpg | 154g | £200 | 37% |
| S-Class Saloon S 450 d 4MATIC270 PS · A9 · listed 2024 | Diesel | 45.6 mpg | 163g | £200 | 37% |
| S-Class Saloon S 500 4MATIC330 PS · A9 · listed 2024 | Petrol | 34.5 mpg | 186g | £200 | 37% |
| S-Class Saloon Mercedes-Maybach S 580370 PS · A9 · listed 2024 | Petrol | 27.4 mpg | 233g | £200 | 37% |
Economy and CO2 are official WLTP figures. Car tax is the yearly rate at current rates for a car first registered in the year listed, before any expensive car supplement. Company car tax is the 2026/27 benefit-in-kind rate. Showing the 15 most recent of 272 versions.
What a Mercedes-Benz S-Class costs to fuel
- petrol, typical official 27.4mpg…
- diesel, typical official 45.6mpg…
Official figures are usually 10–15% better than real-world driving.
Work out a journey in a Mercedes-Benz S-ClassBuying a used Mercedes-Benz S-Class?
Check the MOT history of the exact car: every result, advisory and mileage reading, free.
Compare the Mercedes-Benz S-Class with other luxury cars
Reliability, economy, car tax and running costs side by side.
Other Mercedes-Benz models
Frequently asked questions
›Is the Mercedes-Benz S-Class reliable?
Its MOT record is better than average: the Mercedes-Benz S-Class is 45% less likely to fail than the average car of the same age and mileage, with a reliability score of 181 in our 2024 league (100 is average).
›What are common problems with the Mercedes-Benz S-Class?
The most common MOT fault is “Ball joint: ball joint excessively worn”, found in 2.9% of tests.
›What MPG does the Mercedes-Benz S-Class do?
Official economy for the Mercedes-Benz S-Class ranges from 19 to 61.4mpg across the 272 versions listed by the Vehicle Certification Agency (2004–2025). A typical petrol version manages 27.4mpg and a typical diesel 45.6mpg. Expect 10–15% less in real-world driving.
›How much is road tax on a Mercedes-Benz S-Class?
Any Mercedes-Benz S-Class first registered from April 2017 pays the standard rate of £200 a year after its first year (2026/27 rates). A Mercedes-Benz S-Class registered between March 2001 and March 2017 is taxed on its CO2: £200 to £790 a year.
›How many Mercedes-Benz S-Classes fail their MOT?
16.6% of Mercedes-Benz S-Classes aged 3 to 20 failed their MOT first time in 2024, and 6.3% failed at their first MOT.
Sources: DVSA anonymised MOT tests 2024, all versions of the Mercedes-Benz S-Class combined (Open Government Licence v3.0); official economy and CO2 from Vehicle Certification Agency data, © Crown copyright. VCA cannot accept liability for its accuracy. How we calculate the league.