three piece suits

What the waistcoat changes

A waistcoat does two jobs. It raises the formality of the same cloth by a full step, and it keeps the outfit looking deliberate once the jacket is off — which, at a wedding running from a two o'clock ceremony to a midnight bar, it will be. That is the practical case for three piece at any long event. The aesthetic case is that it narrows the torso and gives the shirt somewhere to sit, so photographs read cleaner.

Getting the waistcoat right

It should sit flat against the shirt with no pulling at the buttons, and it should be long enough to cover the waistband completely, a strip of shirt showing between waistcoat and trouser is the single most common fit error. Leave the bottom button undone on a pointed hem; fasten all of them on a straight hem. If the waistcoat is snug and the jacket is right, take the waistcoat in rather than sizing the whole suit up.

Groom, groomsmen and guests

Grooms usually go three piece, or a tuxedo for a formal evening ceremony. Groomsmen look better one step simpler than the groom rather than identical two piece where the groom wears three, or the same suit with a different tie, so the groom reads first in the photographs. Guests are safest in two piece unless the invitation says otherwise. Start a full party at wedding suits and tuxedos.

Frequently asked questions

A jacket, trousers and a matching waistcoat, all cut from the same cloth. The waistcoat is the only thing that separates it from a two piece suit.

Weddings, ceremonies, formal receptions and any long event where the jacket is likely to come off. The waistcoat keeps the outfit looking finished without it.

Yes, though they read more formal and more traditional than a two piece. They are standard for grooms and common for groomsmen, and less common in a modern office.

Leave the bottom button undone on a pointed waistcoat. On a straight hem, fasten all of them.

Yes, and that is one of the reasons to buy three piece. Keep the tie on if the event is formal.

Flat against the shirt with no pulling at the buttons, and long enough to cover the waistband completely — no shirt showing between the waistcoat and the trousers.

No. Black tie means a dinner suit with satin lapel facing and a bow tie. A three piece is formal daywear, not black tie.