what to wear to a dressy casual wedding
Casual weddings. A casual wedding is the perfect opportunity to wear a cute sundress, a pretty skirt and top, or even nice trousers with a pretty top. But unless the host specifically said that blue jeans are OK, skip them.
He should wear: A tuxedo or a formal dark suit and tie. She should wear: A long dress, a dressy suit, or a formal cocktail-length dress in a dark, neutral tone like brown, gray, or black. This suggests an elegant beach wedding -- so dress to impress, but also dress for the elements (sun, sand, and water).
White-tie is the most formal look for men; it includes a formal tailcoat, a white vest, and a white tie. Black-tie is slightly less formal; men can simply wear a tuxedo, and should take the black tie part literally, wearing an actual black tie (and vest or cummerbund).