2021 Mercedes-AMG GLB 35 Review: The Hot Hatch for Grown-Ups

Dessert is a building opportunity for kids. A small mountain of ice cream is a good start, but what it really needs is some gummy worms, a smattering of marshmallows, and at least two sauces. Maybe throw a slice of cake in there.

The 2021 Mercedes-AMG GLB 35 is that sugary amalgam in four-wheeled form, for adults. You want a family-friendly compact crossover, but you also want a larger one. A hot hatch sounds like fun, but a luxury badge on the nose matters.

The folks in Affalterbach have just the answer. They’ve given the GLB the AMG treatment, addressing all those disparate desires in one cute, squared-off package. A week with the GLB 35 showed off an irresistible blend of performance and practicality, all wrapped up in a package bursting with character.

The GLB as a whole joined the burgeoning Merc family last year. As the name suggests, it splits the difference between the GLA and GLC crossovers, at least in terms of footprint. In practice, it’s quite a unique animal: stubbier than the GLC, with baby Geländewagen vibes, it squeezes in an optional kids-only third row of seats. You won’t find that in either GLA or GLC—or any other compact crossover not named Tiguan or Outlander.

Merc’s front-drive based compact platform underpins the GLB, just as it does the A, CLA, and GLA. For 35 duty, the GLB gets an AMG-specific all-wheel drive system, capable of sending up to 50 percent of the available power to the rear axle. How much is available? An extra-strength 2.0-liter turbocharged four-cylinder sits under that flat hood, pumping out 302 horsepower and 295 pound-feet of torque. That’s as hot as you’ll find in the GLB; unlike its platform-mates, the GLB doesn’t offer a 45 model, at least not yet. An eight-speed dual-clutch transmission is the only transmission choice.

Like a taller hot hatch, essentially. The drivetrain may be front-biased, but the GLB turns in keenly. The AMG-tweaked AWD system shuffles power rearward early and often, keeping the GLB neutral in all but the tightest corners, where it will understeer.

The engine is a firecracker. After a brief bit of turbo lag, it finds its stride around 3,000 rpm, shoving the GLB down the road with a burbly backing soundtrack. In the more athletic drive modes, pops and crackles accompany downshifts, each one slotting home with urgency. Mercedes quotes a run to 62 mph (100 km/h) in 5.2 seconds, and the ol’ butt-dyno suggests that’s accurate, if not slightly conservative.

At lower speeds, the eight-speed dual-clutch can sometimes trip over its own feet, with the off-the-line jerkiness common of this transmission type.

Weighing in at 3,869 pounds (1,755 kilograms), the GLB 35 may have had few gummy-marshmallow-cake sundaes of its own. Nonetheless, it remains composed through corners, tracking straight and true with moderate body lean. Ride quality on the 20-inch wheels was on the firm side of acceptable. Switching to Sport or Sport+ driving modes of course tightened the suspension and steering up. The latter starts to feel too artificial at the most aggressive setting, however.

Have you sat in any other A-Class-related products over the last two or three years? Then congratulations, you should be able to find everything pretty quickly inside the GLB 35.

That’s not a dig. The GLB interior is a fun place to be, all turbine-style air vents and smooth-shifting LED ambient lighting. Material quality is generally good, though door trim and switches feel slightly low-rent at this asking price. The twin-screen setup looks sharp, and thankfully Mercedes has kept the important climate controls just below. Passengers can poke away at the screen, while the driver has the option of using the touchpad on the center console or—my preferred method—the smaller touchpad on the right steering spoke. Front-seat comfort is high, and the Alcantara/leather buckets hold drivers firmly in place through corners.

With that boxy shape, second-row headroom is exceptional. Legroom is good too, with 38.1 inches (968 millimeters) of the stuff in this tester. The second row slides about half a foot, as well. Check the box for the third row and the middle row loses a little over an inch of legroom. Storage space, at a welcome 27.0 cubic feet (764 liters), drops to just 5.0 (141 L) with the extra seating in place.

The GLB’s tech suite is hit and miss; it’ll score more points depending on how much you open your wallet. Even Apple CarPlay and Android Auto support are locked behind an expensive option package in Canada, for example. Augmented reality navigation is very handy in unfamiliar parts of the city: street names and turn instructions overlay a live camera feed in the center screen. The head-up display being optional is disappointing. Same goes for the surprisingly light standard driver assist tech. To get the good stuff, like adaptive cruise control, lane-keep assist, and more, you’ll need to plump for the Driver Assistance Package ($1,700 / $1,700 CAD).

Mercedes’ niche-filling obsession means there isn’t a direct GLB 35 competitor out there. As mentioned above, the only other three-rows in this weight class are the Volkswagen Tiguan and Mitsubishi Outlander. Neither one features a badge with the gravitas of the three-pointed star, however. Performance isn’t even warm, never mind a temperature approaching hot.

Think laterally and more options pop up. Don’t need the extra space? The GLA 35 offers all the same firepower barely contained in a tighter package. There’s even a GLA 45 if the idea of a $55,000 ($61,000 CAD) sub-compact SUV—before options—doesn’t scare you. Maybe you want something a little boxier, but still that size? The Mini Countryman JCW offers a 300-horsepower hit, too.

The GLB recently came off a comparison with its big brother, the GLC. In non-AMG 300 guise, the GLC is a smoother, more traditional luxury SUV experience. The GLC 43 adds emphasis on the “sport” part of “sport utility vehicle,” starting right around $60,000 ($67,000 CAD).

That’s roughly what you’d need for this particular GLB 35, too. While pricing starts at $50,550 including destination ($57,500 CAD without), this well-trimmed tester rang up to the tune of $59,045 ($65,900 CAD, again without destination). Expense remains the biggest stumbling block for the GLB 35. Like that snack-loaded sundae, it’ll cost ya, just in dollars instead of brain freeze and the inevitable sugar crash.

The thing is, the 2021 Mercedes-AMG GLB 35 is one sweet little ride. It’s positively brimming with character, able to supply plenty of smiles along your local back road. The GLB doesn’t sacrifice practicality for fun either, offering up a spacious, stylish interior and lots of storage space. It offers all the flavors you could want in one tidy (if pricey) package.

Go on, chow down.

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