Mercedes-Benz GLA-Class vs Subaru Ascent: Specs Compared

Also searched as Subaru Ascent vs Mercedes-Benz GLA-Class specs — both orientations show this same side-by-side comparison.

The Mercedes-Benz GLA-Class is the more efficient of the two: it reaches 29 mpg combined versus 23 mpg for the Subaru Ascent, a 6 mpg advantage and costs about $50 less per year to fuel.

Across 5 measured categories, the Mercedes-Benz GLA-Class leads in 5. Figures are EPA test data, not manufacturer claims.

2015–2026

Mercedes-Benz GLA-Class

Small Sport Utility Vehicle 4WD · 43 configurations

29mpg combined (best)
All Mercedes-Benz GLA-Class specs

2019–2027

Subaru Ascent

Standard Sport Utility Vehicle 4WD · 18 configurations

23mpg combined (best)
All Subaru Ascent specs

Head-to-head specifications

MetricMercedes-Benz GLA-ClassSubaru Ascent
Best combined MPG29 mpg ✓23 mpg
Best city MPG26 mpg ✓21 mpg
Best highway MPG34 mpg ✓27 mpg
Lowest annual fuel costEPA estimate at 15,000 miles per year$2,600 ✓$2,650
Lowest CO2 output306 g/mi ✓384 g/mi
Engines offeredSIDI; Mild Hybrid, SIDI, SIDI; FFVSIDI
TransmissionsAutomatic (AM8), Automatic (AM7)Automatic (AV-S8)
DrivetrainsAll-Wheel Drive, Front-Wheel Drive, 4-Wheel DriveAll-Wheel Drive
Fuel typesPremium, Premium or E85Regular
EPA classSmall Sport Utility Vehicle 4WDStandard Sport Utility Vehicle 4WD
Years covered2015–20262019–2027
Configurations on record4318

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

Mercedes-Benz GLA-Class vs Subaru Ascent dimensions and size

The Subaru Ascent is 22.4 inches longer than the Mercedes-Benz GLA-Class on a wheelbase 6.3 inches longer, and 551.2 lbs heavier. Both clear the roughly 200 inches of usable length in a standard single garage bay.

Mercedes-Benz GLA-Class versus Subaru Ascent exterior dimensions
DimensionMercedes-Benz GLA-Class (2026)Subaru Ascent (2026)Difference
Length174.4 in196.9 in22.4 in
Width (excl. mirrors)72 in71.7 in0.4 in
Height62.6 in76 in13.4 in
Wheelbase107.5 in113.8 in6.3 in
Curb weight3,869 lbs4,420 lbs551 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.

Mercedes-Benz GLA-Class vs Subaru Ascent: what the numbers mean

Running cost over five years: at the EPA's 15,000-mile-a-year assumption the Mercedes-Benz GLA-Class burns about $2,600 of fuel annually against $2,650 for the Subaru Ascent. That $50 yearly gap compounds to roughly $250 over five years and $400 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 GLA-Class leads in both cycles — 26 mpg city and 34 mpg highway against 21 and 27 mpg — so its fuel-efficiency advantage holds whether you commute in traffic or cover long highway miles.

Powertrain choice: the Mercedes-Benz GLA-Class is recorded with 3 distinct engine configurations (SIDI; Mild Hybrid, SIDI, SIDI; FFV), the Subaru Ascent with 1 (SIDI). Across 43 recorded Mercedes-Benz GLA-Class configurations and 18 for the Subaru Ascent, 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 Mercedes-Benz GLA-Class is offered with All-Wheel Drive, Front-Wheel Drive, 4-Wheel Drive, the Subaru Ascent with All-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 Small Sport Utility Vehicle 4WD and Standard Sport Utility Vehicle 4WD 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 GLA-Class emits 306 g/mile of CO2 versus 384 g/mile for the Subaru Ascent. Emissions track fuel consumption almost exactly, so the cleaner vehicle here is also the cheaper one to fuel.

GLA-Class vs Ascent: common questions

Which is better on gas, the Mercedes-Benz GLA-Class or the Subaru Ascent?

The Mercedes-Benz GLA-Class is the more efficient of the two: it reaches 29 mpg combined versus 23 mpg for the Subaru Ascent, a 6 mpg advantage and costs about $50 less per year to fuel.

Which costs less to run per year?

By EPA estimates at 15,000 miles a year, the Mercedes-Benz GLA-Class runs about $2,600 a year in fuel at its most efficient configuration, versus about $2,650 for the Subaru Ascent — a difference of roughly $50 per year.

What engines do the GLA-Class and Ascent offer?

Mercedes-Benz GLA-Class: SIDI; Mild Hybrid, SIDI, SIDI; FFV. Subaru Ascent: SIDI.

Are they in the same vehicle class?

The EPA classifies the Mercedes-Benz GLA-Class as Small Sport Utility Vehicle 4WD and the Subaru Ascent as Standard Sport Utility Vehicle 4WD, so they aren't a like-for-like match on size.

More GLA-Class comparisons

More Ascent comparisons

Comparison id: mercedes-benz-gla-class-vs-subaru-ascent