Front space in the Fiesta ST is excellent, so all shapes and sizes of driver should be happy with the head and leg room on offer. Ford also includes a decent glovebox, a sizeable cubby at the base of the dashboard and generous door pockets in which to store odds and ends.
In the back, it matches the Polo GTI for head and leg room but not interior width. It's definitely roomier than the Peugeot 208 GTI but would still be deemed snug by a couple of taller adults forced to travel together. If you expect to make regular use of the rear seats, we advise you go for the five-door bodystyle, because the three-door is far more restrictive when getting in and out, and its long doors are a pain to open in a tight parking space.
The Fiesta ST's boot trumps the Polo GTI's for luggage space (the GTI's boot is smaller than that of the regular Polo). The only problem is that if you drop the Fiesta’s 60/40-split folding rear seats, they leave an awkward stepped floor. We suggest adding the optional variable-height boot floor, which can be raised to smooth this out.