The Dress Code, Decoded: What to Wear to a White-Tie, Black-Tie or Semi-Formal Wedding

What it signals. The most formal dress code there is, and the rarest on a wedding invitation, usually reserved for grand venues and formal schedules.

What to wear. A floor-length evening gown, with long evening gloves by tradition, removed for eating; above-the-elbow opera gloves are the classic length, though the gown decides. Fabrics with real presence suit the occasion, such as duchess satin, silk faille, mikado or richly embroidered tulle, with embellishment that is rich but refined.

Where there is room. Less than in any other code. The freedom lies in silhouette: a full skirt and a sculpted column can be equally correct, provided the hem is floor-length and the finish considered.

What it signals. A well-established code for formal evening weddings, and the one most often printed on an invitation.

What to wear. A floor-length gown, polished rather than ceremonial: a sleek column, a fluid A-line or a softly draped silhouette in satin, crepe, chiffon or embellished tulle.

Where there is room. In degree rather than length. A strong color, a single striking detail or a more restrained finish all read as appropriate. When the invitation says black tie optional, a floor-length gown remains the most natural choice, while an elegant cocktail dress or refined evening separates may also suit, depending on the venue.

What it signals. A celebration that is polished but less structured, where a full-length gown is not expected.

What to wear. An elegant midi, a tea-length dress or a polished cocktail dress in crepe, satin, lace or chiffon. For an evening celebration, a simple, fluid floor-length dress can work too, provided its construction and embellishment stay understated enough not to feel ceremonial.

Where there is room. More than in either formal code. A daytime wedding calls for lighter colors and fabrics, while an evening one can take richer tones and a little more shine, as long as the finish stays refined.