Genesis G90 vs Mercedes-Benz S-Class: Specs Compared
Also searched as Mercedes-Benz S-Class vs Genesis G90 specs — both orientations show this same side-by-side comparison.
The Mercedes-Benz S-Class is the more efficient of the two: it reaches 26 mpg combined versus 21 mpg for the Genesis G90, a 5 mpg advantage and costs about $700 less per year to fuel.
Across 5 measured categories, the Mercedes-Benz S-Class leads in 5. Figures are EPA test data, not manufacturer claims.
2015–2027
Mercedes-Benz S-Class
Large Cars · 106 configurations
Head-to-head specifications
| Metric | Genesis G90 | Mercedes-Benz S-Class |
|---|---|---|
| Best combined MPG | 21 mpg | 26 mpg ✓ |
| Best city MPG | 18 mpg | 24 mpg ✓ |
| Best highway MPG | 26 mpg | 31 mpg ✓ |
| Lowest annual fuel costEPA estimate at 15,000 miles per year | $3,600 | $2,900 ✓ |
| Lowest CO2 output | 426 g/mi | 106 g/mi ✓ |
| Engines offered | SIDI & PFI, SIDI & PFI; Mild Hybrid, SIDI | SIDI; Mild Hybrid, 6.0, SIDI; PHEV, SIDI |
| Transmissions | Automatic (S8) | Automatic 9-spd, Automatic 7-spd |
| Drivetrains | All-Wheel Drive, Rear-Wheel Drive | All-Wheel Drive, 4-Wheel Drive, Rear-Wheel Drive |
| Fuel types | Premium | Premium, Premium and Electricity |
| EPA class | Large Cars | Large Cars |
| Years covered | 2017–2026 | 2015–2027 |
| Configurations on record | 32 | 106 |
Source: EPA fuel economy records via fueleconomy.gov. Best-case values across all recorded configurations for each model.
Genesis G90 vs Mercedes-Benz S-Class dimensions and size
The Mercedes-Benz S-Class is 0.4 inches longer than the Genesis G90 on a wheelbase 1.2 inches longer, and 119 lbs lighter. At over 200 inches, the larger of the two is past the comfortable limit of a standard 192-inch single garage bay once you allow walking room.
| Dimension | Genesis G90 (2026) | Mercedes-Benz S-Class (2026) | Difference |
|---|---|---|---|
| Length | 207.9 in | 208.3 in | 0.4 in |
| Width (excl. mirrors) | 58.7 in | 76.8 in | 18.1 in |
| Height | 76 in | 59.1 in | 16.9 in |
| Wheelbase | 125.2 in | 126.4 in | 1.2 in |
| Curb weight | 4,859 lbs | 4,740 lbs | 119 lbs |
Width excludes mirrors; add 8–12 inches for mirrors out. Figures are for the newest model year on record for each vehicle. See both drawn to scale.
Genesis G90 vs Mercedes-Benz S-Class: what the numbers mean
Running cost over five years: at the EPA's 15,000-mile-a-year assumption the Mercedes-Benz S-Class burns about $2,900 of fuel annually against $3,600 for the Genesis G90. That $700 yearly gap compounds to roughly $3,500 over five years and $5,600 over eight — often more than the price difference between two trims of the same vehicle, and the single largest running-cost line item separating these two.
City and highway economy: the Mercedes-Benz S-Class leads in both cycles — 24 mpg city and 31 mpg highway against 18 and 26 mpg — so its fuel-efficiency advantage holds whether you commute in traffic or cover long highway miles.
Powertrain choice: the Genesis G90 is recorded with 3 distinct engine configurations (SIDI & PFI, SIDI & PFI; Mild Hybrid, SIDI), the Mercedes-Benz S-Class with 4 (SIDI; Mild Hybrid, 6.0, SIDI; PHEV). Across 32 recorded Genesis G90 configurations and 106 for the Mercedes-Benz S-Class, the wider the engine spread the more the real-world fuel efficiency depends on which version you actually buy, so check the specific model year and drivetrain rather than the headline number.
Drivetrain and class: the Genesis G90 is offered with All-Wheel Drive, Rear-Wheel Drive, the Mercedes-Benz S-Class with All-Wheel Drive, 4-Wheel Drive, Rear-Wheel Drive. All-wheel drive typically costs one to two mpg combined against the same vehicle in front- or rear-wheel drive, which is worth remembering when the gap between these two is small. The EPA classes them as Large Cars and Large Cars respectively — the class drives the interior volume, cargo space and passenger space each one is measured against.
Tailpipe emissions: at their cleanest configurations the Mercedes-Benz S-Class emits 106 g/mile of CO2 versus 426 g/mile for the Genesis G90. Emissions track fuel consumption almost exactly, so the cleaner vehicle here is also the cheaper one to fuel.
G90 vs S-Class: common questions
Which is better on gas, the Genesis G90 or the Mercedes-Benz S-Class?
The Mercedes-Benz S-Class is the more efficient of the two: it reaches 26 mpg combined versus 21 mpg for the Genesis G90, a 5 mpg advantage and costs about $700 less per year to fuel.
Which costs less to run per year?
By EPA estimates at 15,000 miles a year, the Mercedes-Benz S-Class runs about $2,900 a year in fuel at its most efficient configuration, versus about $3,600 for the Genesis G90 — a difference of roughly $700 per year.
What engines do the G90 and S-Class offer?
Genesis G90: SIDI & PFI, SIDI & PFI; Mild Hybrid, SIDI. Mercedes-Benz S-Class: SIDI; Mild Hybrid, 6.0, SIDI; PHEV, SIDI.
Are they in the same vehicle class?
Yes — the EPA classifies both the Genesis G90 and the Mercedes-Benz S-Class as Large Cars, so they compete directly.
More G90 comparisons
More S-Class comparisons
Comparison id: genesis-g90-vs-mercedes-benz-s-class