Trunk comparison: Seat Tarraco vs VW Tiguan Allspace

Key Differences
The Seat Tarraco offers significantly more cargo space with the third row upright than the VW Tiguan Allspace: the trunk is 25.6 in or +138% larger when all seats are upright.
Additionally, the Tarraco's trunk opening is 4.3 in or +15% higher and the depth of the cargo area (from loading edge to trunk floor) is 2.4 in or +500% greater than in the Tiguan Allspace.
Smaller differences, below the 10% threshold and hardly noticeable in everyday use, include: the Tiguan Allspace has a 1.2 in (+2%) longer cargo floor with all rear seats folded down, the loading edge of the Tiguan is 0.8 in (+3%) higher above the ground, and width differences at the narrowest point and at the opening are each 0.4 in (+1%) in favor of the Tarraco.
Also, both models are the same length with the first row upright.
Impact on Usability
The large differences in the Tarraco (especially +138% with the third row upright and +500% depth) make it clearly better suited for combined passenger and cargo transport: with three rows occupied, significantly more usable storage space remains for bags, boxes, or luggage, and the greater depth makes it easier to stow taller or bulkier items behind the last row.
The higher opening of the Tarraco (+15%) facilitates loading and unloading bulky or tall cargo without excessive tilting.
The Tiguan Allspace only scores marginally on maximum cargo space when all rear seats are folded (+2% longer cargo floor), which can be useful occasionally for transporting large items but does not represent a pronounced advantage over the Tarraco.
The slightly higher loading edge of the Tiguan (+0.8 in) makes lifting heavy items in slightly less convenient. Width differences are so small that they are practically irrelevant.