One of the questions most frequently asked is if there's some sort of general rule against wearing navy and black. While we are against wearing black shoes with navy suit, the success of this colour pairing in general is a little more complicated than that.

Insufficient contrast is, to the eye, confusing and a little uncomfortable. The problem with navy and black is that a dark navy looks similar enough to black to appear like a matching error. But there are many shades of navy, and the less black your navy looks, generally, the safer it will be as a pairing with black. (This also applies to grey and black, brown and black, etc). That said, there's something kind of cool about deep blues with blacks that approach the limit of visual confusion without quite reaching it, which is why you'll see, for example, midnight blue dinner jackets with black trim.

A good rule of thumb is that if the colours aren't visibly different in the dim morning light of your closet, don't do it.

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