Trunk comparison: BMW 3 Series Touring vs Volvo V90

Biggest Differences (>10%)
The Volvo V90 offers significantly more cargo space in length and width: with the seats folded down, it is 7.5 in (11%) longer, and with the front seats upright, the trunk of the Volvo is 5.5 in (14%) longer than that of the BMW 3 Series Touring.
Additionally, the Volvo is 3.9 in (11%) wider at the narrowest point of the trunk, and the width of the trunk opening is 5.5 in (14%) larger than the BMW. These four differences each exceed 10% and represent the most relevant physical advantages of the V90.
Impact on Usability
The greater length of the Volvo makes it significantly better suited for long items such as slats, skis, boards, or furniture parts — both with folded and upright seats.
The greater usable interior width and wider opening make loading bulky or wide items easier (e.g., several suitcases side by side, wide boxes, strollers) and reduce maneuvering when loading.
For the BMW, the differences in opening height (+0.8 in), trunk depth measurements (+0.4 in), and loading edge height (+0.4 in in favor of the Volvo) are very small and thus hardly noticeable in everyday use.
Practically, these slight deviations mean: the BMW has a minimally higher opening height and a slightly lower loading edge, which can slightly ease lifting heavy items. However, this does not compensate for the significantly greater cargo length and width of the Volvo.
Conclusion: Those who regularly transport long or wide loads or frequently travel fully loaded will find noticeably more flexibility with the Volvo V90. Those who mostly carry smaller luggage and occasionally value somewhat easier handling when lifting will find the BMW 3 Series Touring a sufficiently practical solution — however, the space advantages of the V90 remain decisive for large or bulky loads.