Barrel-aged ales are those that have been aged in a wooden barrel to impart flavors and aromas of wood to the finished product. Most barrels are made of oak, though some brewers will use barrels made from acacia, ash, chestnut or poplar, to name only a few.

Although most ales (and beers in general) are made in steel tanks, barrel aging has become a cult movement as of late, especially from micro brewers, who use a range of casks, from wine barrels to rum barrels to scotch barrels. The finished product will be influenced by the tannins in the barrel as well as the beverage that was previously aged in that container.

Flavored Barrel Aged Ales will have additional flavorings such as spices, herbs, fruits, honey, or chocolate. They are often a bit sweeter than their non-flavored counterparts.