BMW 3 Series vs Mercedes-Benz CLA-Class
The Mercedes-Benz CLA-Class is the more efficient of the two: it reaches 126 mpg combined versus 36 mpg for the BMW 3 Series, a 90 mpg advantage and costs about $1,600 less per year to fuel.
Across 5 measured categories, the Mercedes-Benz CLA-Class leads in 4. Figures are EPA test data, not manufacturer claims.
2015–2027
Mercedes-Benz CLA-Class
Compact Cars · 55 configurations
Head-to-head specifications
| Metric | BMW 3 Series | Mercedes-Benz CLA-Class |
|---|---|---|
| Best combined MPG | 36 mpg | 126 mpg ✓ |
| Best city MPG | 31 mpg | 127 mpg ✓ |
| Best highway MPG | 43 mpg | 124 mpg ✓ |
| Lowest annual fuel costEPA estimate at 15,000 miles per year | $2,200 | $600 ✓ |
| Lowest CO2 output | 158 g/mi ✓ | 273 g/mi |
| Engines offered | SIDI & PFI; Mild Hybrid, SIDI, SIDI; PHEV, SIDI; Mild Hybrid | SIDI; Mild Hybrid, SIDI, SIDI; FFV |
| Transmissions | Automatic (S8), Manual 6-spd | Automatic (A2), Automatic (A1), Automatic (AM8) |
| Drivetrains | Rear-Wheel Drive, All-Wheel Drive | All-Wheel Drive, Rear-Wheel Drive, Front-Wheel Drive |
| Fuel types | Premium, Premium and Electricity, Diesel | Electricity, Premium, Premium or E85 |
| EPA class | Compact Cars | Compact Cars |
| Years covered | 2015–2026 | 2015–2027 |
| Configurations on record | 105 | 55 |
Source: EPA fuel economy records via fueleconomy.gov. Best-case values across all recorded configurations for each model.
3 Series vs CLA-Class: common questions
Which is better on gas, the BMW 3 Series or the Mercedes-Benz CLA-Class?
The Mercedes-Benz CLA-Class is the more efficient of the two: it reaches 126 mpg combined versus 36 mpg for the BMW 3 Series, a 90 mpg advantage and costs about $1,600 less per year to fuel.
Which costs less to run per year?
By EPA estimates at 15,000 miles a year, the Mercedes-Benz CLA-Class runs about $600 a year in fuel at its most efficient configuration, versus about $2,200 for the BMW 3 Series — a difference of roughly $1,600 per year.
What engines do the 3 Series and CLA-Class offer?
BMW 3 Series: SIDI & PFI; Mild Hybrid, SIDI, SIDI; PHEV, SIDI; Mild Hybrid. Mercedes-Benz CLA-Class: SIDI; Mild Hybrid, SIDI, SIDI; FFV.
Are they in the same vehicle class?
Yes — the EPA classifies both the BMW 3 Series and the Mercedes-Benz CLA-Class as Compact Cars, so they compete directly.
More 3 Series comparisons
Comparison id: bmw-3-series-vs-mercedes-benz-cla-class