24 MPG combined is an acceptable number, even admirable, considering what the 2021 Mercedes-Benz S500 4matic represents: effortless performance wrapped in luxury, technology, and advanced safety features. No one buys an S-Class expecting Prius-like fuel consumption, but neither are they willing to accept egregious gas-guzzling. The S500 finds a reasonable middle ground, offering ample power and plushness with respectable fuel economy for its class. It’s a car for executives, entrepreneurs, and individuals who prioritize refined driving over outright efficiency and who likely have the means to absorb the cost of premium fuel.

City and highway performance

The EPA estimates the S500 4matic achieves 20 MPG in the city and 29 MPG on the highway. These figures reflect the reality of stop-and-go traffic and sustained cruising speeds. The 9-speed automatic transmission plays an important role in maximizing efficiency, keeping the engine in its optimal rev range. While 20 MPG in the city might seem low, consider the weight of the vehicle and the performance capabilities of its 3.0L turbocharged inline-six engine. The S500 truly shines on the open road.

The 29 MPG highway rating makes long journeys comfortable and reasonably economical, perfect for cross-state business trips or weekend getaways.

Annual fuel cost

According to the EPA, the annual fuel cost for the 2021 Mercedes-Benz S500 4matic is $2,400. This figure is based on driving 15,000 miles per year and using national average fuel prices for premium unleaded gasoline. It’s important to remember this is an estimate, and your actual fuel costs may vary depending on your driving habits, the type of roads you frequent, and fuel prices in your area. However, the $2,400 figure provides a useful benchmark for budgeting fuel expenses.

Real-world expectations

While the EPA estimates provide a good starting point, real-world fuel economy can differ. Aggressive acceleration, frequent hard braking, and constant city driving will inevitably reduce MPG. Prioritizing smooth acceleration, anticipating traffic flow, and maximizing highway driving can improve fuel economy closer to the EPA estimates, or even exceed them. Owners who prioritize fuel economy in their driving style can likely achieve results closer to the 29 MPG highway rating, while those who frequently exploit the engine’s power output may see numbers closer to the 20 MPG city rating. Observing the S500 MPG across all years can also help you gauge expectations based on past performance.

How it compares

The Mercedes-Benz S500’s fuel economy stacks up reasonably well against its competitors. The BMW 740i, with its similarly sized 3.0L inline-six, achieves an EPA-estimated 22 MPG combined, slightly lower than the S500’s 24 MPG. The Audi A8, another key rival, returns similar figures, hovering around the low-to-mid 20s for combined MPG. The Lexus LS 500, with its V6 engine, manages around 21 MPG combined. These figures are important to potential buyers because they demonstrate that the S500 doesn’t significantly penalize you at the pump compared to similar flagship sedans. For those willing to consider plug-in hybrid options, cars like the BMW 745e offer significantly better fuel economy in electric-only mode, but at a higher initial purchase price and with range limitations.

Tips to maximize efficiency

Take advantage of the S500’s driving modes. The “Eco” mode optimizes engine and transmission settings for maximum fuel efficiency, reducing throttle response and shifting to higher gears earlier. It might not be the most engaging driving experience, but it can make a noticeable difference in MPG, especially during long highway cruises.

Minimize unnecessary weight in the vehicle. Carrying around heavy items in the trunk or backseat adds extra load to the engine, reducing fuel economy. Remove any items you don’t need to improve efficiency.

Ensure your tires are properly inflated. Underinflated tires increase rolling resistance, forcing the engine to work harder and consuming more fuel. Check your tire pressure regularly and inflate to the recommended levels specified on the doorjamb sticker.

Practice smooth and consistent driving. Avoid harsh acceleration and braking. Anticipate traffic flow to maintain a steady speed and minimize unnecessary stop-and-go driving. This is easier said than done in congested areas, but with conscious effort, you can improve your fuel economy. Review all Mercedes Benz fuel economy data to see how other models respond to different driving styles.