These days, the two terms are often used interchangeably, but they’re not the same thing. Some brands will even wrongly use the term button-down to refer to a button-up shirt, with the most egregious example off the top of my head being Criquet, which has an entire section of “Button Downs” on its website without a single actual button-down shirt on offer.
So what difference does it make whether you wear a button-down or button-up shirt?
All Buttoned Up
Traditionally, button-down shirts are considered more casual than their button-up counterparts. A button-up shirt, which typically uses hidden collar stays in place of buttons to keep its collar in place, looks cleaner than a button-down and should be your shirt of choice whenever you’re wearing a tie.
Button-up shirts also tend to be made from finer weaves of fabric, like twill, that give them a smoother hand feel and crisper appearance. Again, this makes them better for more formal occasions.
Meanwhile, button-down shirts are generally worn without a tie, and their fabrics tend to be more rugged and coarser. Think of the classic Oxford shirt. It’s meant to be comfortable and casual, with its Oxford-cloth weave and button-down collar acting as defining traits.
