Black tie by lori : Formal Wear Etiquette Guide : Contemporary

Participant	Very Formal Evening	Formal Evening	Very Formal Daytime	Semi Formal Evening
Groom	Black Full-dress or other color tailcoat applicable. Formal shirt, vest or cummerbund. If wearing black full-dress, wear white wing collar shirt with white vest and bow tie.	Tuxedo or tailcoat in range of colors - dark for fall/winter, lighter shades for spring/summer - or white for any time of year. Formal shirt should be white.	Updated cutaway in light grey shades with striped matching trousers, white formal shirt, ascot or tie.	Tuxedo or tailcoat in range of colors - dark for fall/winter, lighter shades for spring/summer or tropical climates.
Best Man, Groomsmen, Ushers, Juniors, Junior Groomsmen	Similar to groom, or same as ushers, or in a classic tuxedo.	Similar tailcoats or tuxedos to groom. Choose colored vests to match bridesmaid dresses.	Similar to groom in style or can wear matching stroller coats with striped or matching trousers.	Similar to the groom. Coordinated in color with bridesmaid dresses.
Fathers, Grandfathers	Same as groom or same as ushers, or in a classic tuxedo.	Similar to ushers or in classic tuxedo.	Same as groom or same as ushers, or in classic tuxedo.	Either similar to male attendants or own choice of tux.
Ring Bearers	Identical to groom.	Identical to groom.	Identical to groom.	Identical to groom.
Guests	Formalwear similar to groom. Consider specifying 'Black Tie Invited' on invitation; guests should wear black tuxedos.	Formalwear optional. Consider specifying 'Black Tie Invited' on invitations.	Formalwear optional.	Formalwear optional.