Trunk comparison: Audi A4 Avant vs Kia Stonic

Key Differences (highlighted: >10%)

Cargo volume/length with seats folded down: The Audi A4 Avant offers a cargo area that is 18.1 in longer, which is +34% compared to the Kia Stonic.

Cargo volume/length with front seats upright: With the front seats upright, the Audi is even 14.2 in longer, which is +52% more usable length than in the Kia.

Trunk depth (from loading edge to trunk floor): The Kia Stonic has a cargo floor that is 5.1 in deeper than the Audi, stated as +260% — significantly deeper interior space between the loading edge and floor.

Loading edge height above the road: The Kia’s loading edge sits 5.5 in higher than the Audi’s, which is +22%.

Impact on Usability

The Audi A4 Avant clearly has the advantage when it comes to length and thus transporting long or bulky items. The 34% or 52% larger cargo area (depending on seat position) allows for longer items, flat-lying mattresses, furniture parts, or more stretched luggage without restacking.

The Kia Stonic offers significantly more vertical depth between the loading edge and trunk floor, making it easier to stack taller items near the opening.

However, this advantage is offset by a noticeably higher loading edge: the 5.5 in higher lift height makes loading heavy items into the trunk more strenuous and complicates easily sliding large loads through.

The differences in cargo opening width (+1.2 in in favor of Audi) and the narrowest trunk width (+2.4 in in favor of Kia) are under 10% and are hardly decisive for usability in practice.

Conclusion

For regular transport of long or bulky items and easy loading and unloading, the Audi A4 Avant is the more practical choice.

Those who need more vertical depth directly behind the loading edge (e.g., tall stacks near the opening) and lift heavy loads less often will find the Kia Stonic a suitable, more compact candidate — albeit with the limitation of the higher loading edge.