Trunk comparison: Seat Ibiza vs VW ID.3

Key Differences
In a direct trunk comparison, three differences stand out clearly: The VW ID.3 offers an 4.3 in (≈16%) longer cargo floor length with the first row upright than the Seat Ibiza. The Seat Ibiza, on the other hand, has a 1.2 in (≈19%) greater depth between the loading edge and trunk floor.
Additionally, the loading edge of the VW ID.3 sits 3.1 in (≈12%) higher above the road than that of the Seat Ibiza. Other differences (e.g., length with folded seats, width dimensions, height of the trunk opening) are below the 10% mark and therefore smaller.
Impact on Usability
The longer cargo floor of the ID.3 with the rear seat upright makes it more practical for longer items or multiple suitcases without folding down the rear seats (e.g., skis, longer boxes). Those who frequently transport bulky but long items and want to keep the rear seat have an advantage with the ID.3.
The greater depth of the Seat Ibiza means more usable interior space between the loading edge and floor: this facilitates stacking taller luggage and increases the effective loading height inside.
For transporting bulky, less deep items or several suitcases stacked on top of each other, the Ibiza is often more practical.
The higher loading edge on the ID.3 makes loading heavy items more strenuous because they must be lifted higher.
The Ibiza, with its lower loading edge, is more ergonomic when lifting heavy or bulky loads; the combination of lower loading edge height and greater depth also favors securely stowing heavy items closer to the vehicle floor.
Conclusion: The ID.3 scores with usable length with the rear seat upright, the Seat Ibiza with interior depth and easier, more ergonomic loading. Which option fits better depends on typical cargo (long vs. bulky/heavy items).