Even tall adults should find no issues in the front of the 3; there's plenty of leg and shoulder room, and even if you fit the optional sunroof you're unlikely to be troubled by a shortage of head room unless you're well over six feet tall.
There's a decent line-up of storage areas, too, including bottle holders in both doors, a rubber-coated 'sticky' area beyond the gear lever and a reasonably deep glovebox that has room for the owner's manual and a small drinks bottle.
There's also a deeper bin beneath the armrest; it's not lined, though, so any of its contents are likely to rattle around against the hard plastic finish. Nor is there any storage on top of the fascia, because the central display takes up that space.
Mazda 3 rear space
The 3's rear accommodation is a bit of a mixed bag. There is a decent amount of leg and knee room, and the cabin is wide enough for two adults to sit beside each other in comfort. It's tighter for three grown-ups, though, and even if you're there on your own, you may feel slightly hemmed in by the narrowing window line and the thick rear pillar.
There's not much storage space in the back either – just a couple of door pockets, each big enough for a mid-sized drinks bottle, and netting to hold magazines or books.
Mazda 3 seating flexibility
Mazda makes great claims of a 'flexible seating system', but in truth there's nothing here to set the 3 apart from its rivals. The rear seat is split 60/40 and it folds to a pretty flat position, making it easy to slide in longer loads. It's disappointing that you need to open the rear doors to access the lowering release handles, though; you can't perform this action standing at the entrance to the boot itself.
Mazda 3 boot space
The 3 hatchback's boot is slightly larger than a VW Golf's, at 364 litres with the rear seats in place and 1231 litres with them folded. In practical terms that's more than enough for a large weekly shop to sit behind the seats, and you shouldn't have too much trouble squeezing in a set of golf clubs or the chassis and seat of a buggy.
The space is reasonably square, although the rear wheel housings do intrude at the side and Mazda doesn't supply any baggage hooks to keep your shopping from rolling around. There's a high lip to lift loads over, too, which won't be helpful if you're dealing with heavy items.
The 3 Fastback version (in effect a small saloon) has a slightly larger overall capacity (419 litres) but while the bootlid does move right up out of the way when you open it, the aperture that it leaves still isn't anywhere near as helpful as the hatchback's.