Trunk comparison: Ford S-MAX vs Kia Stonic

Biggest Differences

Several clear differences in the trunk stand out in the comparison: The Ford S‑Max offers significantly more length with the seats folded down — +24 in (45%) — and also significantly more cargo volume in the longitudinal direction with the first row of seats upright — +16.9 in (62%) — compared to the Kia Stonic.

The trunk opening of the S‑Max is also higher than that of the Stonic — +5.5 in (18%).

On the other hand, the loading edge of the Kia sits significantly higher above the road — +7.9 in (35%) — and the depth from the loading edge to the trunk floor is significantly greater in the Kia — +5.9 in (500%).

Smaller differences such as the narrowest trunk width (+0.8 in, 2%) or the opening width (+2.8 in, 7%) are under 10% and thus less relevant.

Impact on Usability

The greater loading length of the S‑Max (both with folded seats and with the first row upright) makes it significantly more flexible for long items like slats, furniture parts, or skis; those who regularly transport bulky or long cargo benefit from the S‑Max.

The higher trunk opening of the S‑Max also makes loading tall or bulky items easier because more clearance height is available.

In the Kia Stonic, the higher loading edge and the greater depth between the loading edge and floor combine: Lifting heavy items requires more effort because the loading edge is about 7.9 in higher.

The greater depth means that loaded items sink further into the trunk — this can make securing cargo easier and potentially create more usable height in the upper area, but it complicates handling (e.g., lifting heavy luggage out again).

In summary: For users who frequently transport long or tall items or value easy loading, the Ford S‑Max is the more practical choice. The Kia Stonic can be advantageous with its deeper loading floor when storing bulky but not too heavy items, but it is less comfortable for heavy loads due to the higher loading edge.