Waistcoat Rules

There is nothing wrong with a double-breasted waistcoat. A single breast is more conventional and normal, and a double is more formal – as it harks back to the waistcoats on full fig, or white tie, which were often double breasted.

As to the colour of the waistcoat, the normal and more conventional colour would be black. In the same material as the jacket, with the same grosgrain on the lapels (usually a shawl collar ending in squared-off ends). There is, however, a lot of flexibility here. The waistcoat could be collarless and it could be entirely in grosgrain. It could also be backless or not.

A white piqué waistcoat would be more formal and unusual. Nothing wrong with it, but generally white waistcoats were worn with white tie and black with black tie. But then, strictly speaking you could wear a white bow tie with black tie, as counter-intuitive as it seems. Personally, I would rather like a white waistcoat as it is not incorrect and is a little different.

However, the most important thing is the relationship between the waistcoat and shirt. The waistcoat is made to fit and suit a particular shirt, and this must be born in mind. So a white waistcoat, being very formal, must be worn with a stiff-fronted shirt and wing collar (also formal). Some may argue that the collar should be starched and detachable (very formal). With a black waistcoat you have a little more freedom – fold-down or wing collar is fine.

Also bear in mind the shape of the shirtfront – an oval front best suits a waistcoat with an oval neckline. And a straight up-and-down, pleated shirtfront usually suits a cummerbund best – both being less formal than the options just mentioned.

So the key is balancing the formality of your outfit. And match the waistcoat to the shirt, not to the jacket.