William Frederick "Bill" Rieflin (born September 29, 1960) is an American musician.
Rieflin came to prominence in the 1990s for his work mainly as a drummer with many notable groups (particularly in the industrial rock and industrial metal scenes) including Ministry, the Revolting Cocks, Lard, KMFDM, Pigface, Swans, Chris Connelly, and Nine Inch Nails.