Trunk comparison: Citroen C3 vs Mercedes Benz GLB

Key Differences

The Mercedes‑Benz GLB offers significantly more cargo space in length and opening: with the seats folded down, the GLB's trunk is +16.1 in (30%) longer, and with the first row upright, it is +11 in (42%) longer than the Citroën C3. The GLB's trunk opening is also higher and wider: the opening height is +3.5 in (11%) above that of the C3, and the opening width is +7.1 in (20%) larger.

In contrast, the Citroën C3 has a significantly greater depth between the loading edge and the trunk floor: this depth is +4.3 in (92%) greater in the C3 than in the GLB.

Smaller differences (under 10%) include: the loading edge of the C3 is only +2.4 in (8%) higher above the road than in the GLB, and the narrowest width of the trunk is only +3.5 in (9%) larger in the GLB — these values have less impact on everyday use.

Impact on Usability

For long or bulky items (furniture, boards, skis, etc.) and when transporting with folded seats, the GLB is clearly better suited: the significantly longer cargo floor combined with the larger opening height and width makes it easier to load long, tall, or wide items and increases flexibility when loading.

Also in everyday use (shopping, stroller, luggage), the larger cargo space with the rear seat upright provides noticeably more usable storage space.

The Citroën C3, on the other hand, scores with a deeper loading well: the greater depth (loading edge → trunk floor) creates more usable volume vertically and allows items to be stored deeper (better concealment of luggage, less visibility of cargo).

However, the C3 combines this with a slightly higher loading edge (+2.4 in), which makes lifting heavy loads into the trunk ergonomically less favorable.

Practical consequence: Those who frequently transport long or bulky loads or need a lot of variable storage space (families, tradespeople, occasional moves) are better served by the GLB.

Those who mainly drive in the city and daily life and benefit from a deeper loading well (submerged storage, less tipping of items) may prefer the C3 — but will have to lift items slightly higher more often.