Alfa Romeo Giulia vs Mercedes-Benz S-Class: Specs Compared

Also searched as Mercedes-Benz S-Class vs Alfa Romeo Giulia specs — both orientations show this same side-by-side comparison.

The Alfa Romeo Giulia is the more efficient of the two: it reaches 27 mpg combined versus 26 mpg for the Mercedes-Benz S-Class, a 1 mpg advantage and costs about $100 less per year to fuel.

Across 4 measured categories, the Alfa Romeo Giulia leads in 3. Figures are EPA test data, not manufacturer claims.

2017–2026

Alfa Romeo Giulia

Midsize Cars · 28 configurations

27mpg combined (best)
All Alfa Romeo Giulia specs

2015–2027

Mercedes-Benz S-Class

Large Cars · 106 configurations

26mpg combined (best)
All Mercedes-Benz S-Class specs

Head-to-head specifications

MetricAlfa Romeo GiuliaMercedes-Benz S-Class
Best combined MPG27 mpg ✓26 mpg
Best city MPG24 mpg24 mpg
Best highway MPG33 mpg ✓31 mpg
Lowest annual fuel costEPA estimate at 15,000 miles per year$2,800 ✓$2,900
Lowest CO2 output330 g/mi106 g/mi ✓
Engines offeredSIDISIDI; Mild Hybrid, 6.0, SIDI; PHEV, SIDI
TransmissionsAutomatic 8-spdAutomatic 9-spd, Automatic 7-spd
DrivetrainsAll-Wheel Drive, Rear-Wheel DriveAll-Wheel Drive, 4-Wheel Drive, Rear-Wheel Drive
Fuel typesPremiumPremium, Premium and Electricity
EPA classMidsize CarsLarge Cars
Years covered2017–20262015–2027
Configurations on record28106

Source: EPA fuel economy records via fueleconomy.gov. Best-case values across all recorded configurations for each model.

Alfa Romeo Giulia 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 Alfa Romeo Giulia burns about $2,800 of fuel annually against $2,900 for the Mercedes-Benz S-Class. That $100 yearly gap compounds to roughly $500 over five years and $800 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 versus highway split: the Mercedes-Benz S-Class is the stronger commuter at 24 mpg city, while the Alfa Romeo Giulia pulls ahead on the interstate at 33 mpg highway. If most of your driving is stop-and-go traffic the city figure is the one to weigh; for long-distance highway mileage the reverse is true, and the two vehicles effectively swap places depending on how you drive.

Powertrain choice: the Alfa Romeo Giulia is recorded with 1 distinct engine configuration (SIDI), the Mercedes-Benz S-Class with 4 (SIDI; Mild Hybrid, 6.0, SIDI; PHEV). Across 28 recorded Alfa Romeo Giulia 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 Alfa Romeo Giulia 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 Midsize 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 330 g/mile for the Alfa Romeo Giulia. Emissions track fuel consumption almost exactly, so the cleaner vehicle here is also the cheaper one to fuel.

Giulia vs S-Class: common questions

Which is better on gas, the Alfa Romeo Giulia or the Mercedes-Benz S-Class?

The Alfa Romeo Giulia is the more efficient of the two: it reaches 27 mpg combined versus 26 mpg for the Mercedes-Benz S-Class, a 1 mpg advantage and costs about $100 less per year to fuel.

Which costs less to run per year?

By EPA estimates at 15,000 miles a year, the Alfa Romeo Giulia runs about $2,800 a year in fuel at its most efficient configuration, versus about $2,900 for the Mercedes-Benz S-Class — a difference of roughly $100 per year.

What engines do the Giulia and S-Class offer?

Alfa Romeo Giulia: SIDI. Mercedes-Benz S-Class: SIDI; Mild Hybrid, 6.0, SIDI; PHEV, SIDI.

Are they in the same vehicle class?

The EPA classifies the Alfa Romeo Giulia as Midsize Cars and the Mercedes-Benz S-Class as Large Cars, so they aren't a like-for-like match on size.

More Giulia comparisons

More S-Class comparisons

Comparison id: alfa-romeo-giulia-vs-mercedes-benz-s-class