William Edward Fichtner (born November 27, 1956) is an American actor. Born in New York, he started his career with supporting appearances in Virtuosity (1995), Heat and Strange Days (both 1995). A prolific character actor in film, Fichtner is recognized for memorable performances in Contact (1997), Armageddon (1998), Go (1999), The Perfect Storm (2000), Black Hawk Down (2001), Crash (2004), and The Longest Yard (2005).

In 2005, Fichtner starred as Sheriff Tom Underlay in Invasion. He later appeared as Alexander Mahone in Prison Break, Carl Hickman in Crossing Lines, and Adam Janikowski in Mom.