From hamptons.guestofaguest.com:
The summer season's barely begun, and already we've seen a slew of celebrations. As nothing ruins an ACRIA party like a misjudged Marc Jacobs, I decided to assemble a little tip sheet. Just what is the difference between a soirée and a gala, a benefit and a fundraiser? Read on to find out, and to find which will be getting the most usage....
A "soirée" is a party or gathering held in the evening, and always at least cocktail attire if not black tie. Wear: Fun young talent (Temperley, L'Wren Scott, Rodarte), or well-chosen vintage.
A "benefit" is a party/performance for a charitable cause, and it's usually held in the evening or night, often on a Sunday. Wear: Understated (but recognizable) elegance.