American television and film actor Will McCormack was born in 1974.  He earned a bachelor's degree in English at Trinity College located in Hartford, Connecticut.  Will McCormack is the younger brother of The West Wing and ER actress Mary McCormack.

He made his big screen debut in the independent film Colin Fitz, in which he acted alongside his sister Mary.  The movie earned awards and recognitions from various film festivals such as the Austin Film Festival, the Florida Film Festival, the Long Island Film Festival and WorldFestHouston.  It was also nominated for the Grand Jury Prize Award at the 1997 Sundance Film Festival.  In 1998, Will was cast as Chuck McCormack in Harvest, another indie film which starred Dawson's Creek lead actor James Van Der Beek.  Among Will's other films are Boiler Room, Pretzel, American Outlaw, Elf, Prime, Syriana and Must Love Dogs to name a few.

In 1999, he played the recurring role of Jason La Penna on the highly acclaimed HBO series The Sopranos.  He was also seen on the FX Network's crime drama The Shield and on the CBS popular show CSI: NY.

In 2001, he was featured in the pages of TV Guide.

Leo Spiller is played by Will McCormack on FX's drama series Dirt.  Leo is the younger brother of DirtNow editor-in-chief Lucy Spiller and he finds her sister's career destructive and petty.  He appears to cope better with their father's suicide than Lucy has.  Leo meets movie actor Jack Dawson when he decorates the star's house and the two immediately have a secret gay relationship.  When Leo finds out that Jack is cheating on him, he convinces Lucy to expose the actor's sexuality in her magazine, and she does, putting the story right at the front page of her glossy tabloid.  Leo eventually regrets his actions after seeing the effects on Jack's children and wife.