Mercedes-Benz SL-Class vs Mazda MX-5

The Mazda MX-5 is the more efficient of the two: it reaches 30 mpg combined versus 23 mpg for the Mercedes-Benz SL-Class, a 7 mpg advantage and costs about $750 less per year to fuel.

Across 5 measured categories, the Mazda MX-5 leads in 5. Figures are EPA test data, not manufacturer claims.

2015–2027

Mercedes-Benz SL-Class

Two Seaters · 40 configurations

23mpg combined (best)
All Mercedes-Benz SL-Class specs

2015–2026

Mazda MX-5

Two Seaters · 25 configurations

30mpg combined (best)
All Mazda MX-5 specs

Head-to-head specifications

MetricMercedes-Benz SL-ClassMazda MX-5
Best combined MPG23 mpg30 mpg
Best city MPG21 mpg27 mpg
Best highway MPG28 mpg36 mpg
Lowest annual fuel costEPA estimate at 15,000 miles per year$3,300$2,550
Lowest CO2 output379 g/mi298 g/mi
Engines offeredSIDI, SIDI; Mild Hybrid, SIDI; PHEV, 6.0SIDI, 2.0
TransmissionsAutomatic 9-spd, Automatic 7-spdAutomatic (S6), Manual 6-spd, Manual 5-spd
DrivetrainsAll-Wheel Drive, Rear-Wheel DriveRear-Wheel Drive
Fuel typesPremium, Premium and ElectricityPremium
EPA classTwo SeatersTwo Seaters
Years covered2015–20272015–2026
Configurations on record4025

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

SL-Class vs MX-5: common questions

Which is better on gas, the Mercedes-Benz SL-Class or the Mazda MX-5?

The Mazda MX-5 is the more efficient of the two: it reaches 30 mpg combined versus 23 mpg for the Mercedes-Benz SL-Class, a 7 mpg advantage and costs about $750 less per year to fuel.

Which costs less to run per year?

By EPA estimates at 15,000 miles a year, the Mazda MX-5 runs about $2,550 a year in fuel at its most efficient configuration, versus about $3,300 for the Mercedes-Benz SL-Class — a difference of roughly $750 per year.

What engines do the SL-Class and MX-5 offer?

Mercedes-Benz SL-Class: SIDI, SIDI; Mild Hybrid, SIDI; PHEV, 6.0. Mazda MX-5: SIDI, 2.0.

Are they in the same vehicle class?

Yes — the EPA classifies both the Mercedes-Benz SL-Class and the Mazda MX-5 as Two Seaters, so they compete directly.

More SL-Class comparisons

Comparison id: mercedes-benz-sl-class-vs-mazda-mx-5