We see them on menus and beer lists: Beers labeled Trappist Ales. Others called Abbey Ales. What's the difference? To be called a Trappist Ale, the beverage must be brewed by the Roman Catholic order of cloistered monks known as Trappists. Of the 174 Trappist monasteries, currently only 7 of them brew beer: Chimay, Achel, Orval, Rochefort, Westmalle, Koningshoeven and Westvleteren. All of the Trappist beers are Belgian, with the exception of the Dutch Koningshoeven.
Abbey Ales are created in a similar “monastic style” to the Trappists Ales but are not brewed by Trappist monks. To be a Certified Belgian Abbey Beer, the beer it must be brewed under license to an existing or abandoned abbey. The monastery is allowed to be involved in some aspect of the business and a portion of the profits must go to the abbey. Some of the better-known abbey beers include Leffe (which is the abbey brand of Stella Artois), Grimbergen and Maredsous (the abbey brand of Duvel).
So now you know. Feel free to impress your friends with this new-found beer knowledge!