Jeff was born in Toronto, Canada and attended Ryerson University for Theatre.
He worked on stage in Anne Of A Thousand Days, Play It Again Sam, Romeo and Juliet and in the Toronto Premier of Martin Sherman's play Bent.
He moved to New York to study with Stella Adler, Michael Kahn, and Eli Rill.
Director Paul Lynch cast him in the horror film classic Prom Night (1980).
Wincott's big break came as the Italian hot headed rookie Detective Frank Giambone in the TV series Night Heat for which he was nominated for Outstanding Lead Actor in A Drama Series.
Wincott, a black belt in Taekwondo, became sought after not only as a martial artist but one that could act. Wincott went on to star as the protagonist of motion pictures such as Martial Law 2, Deadly Bet (1992), Mission of Justice (1992), Martial Outlaw (1993), Open Fire (1994), Killing Machine (1994), No Exit (1995), Street Law (1995), The Donor (1995), Last Man Standing (1995), When The Bullet Hits the Bone (1996), Profile For Murder (1996), and Universal Soldier II (1998) and III (1999).
Wincott guest-starred on the TV series JAG, 24, NCIS, Cold Squad, The Wire, Person Of Interest, Blue Bloods, and The Good Wife.
In the films The Invasion, S.W.A.T., Lake City, The Undertakers Wedding, and Unstoppable.
Wincott has a recurring role portraying Jimmy Cacuzza, leader of the Mafia family (Cacuzza crime family) who buys guns from SAMCRO on the hit TV series Sons Of Anarchy (2008-2013) .
He was hired by Rockstar Games as the voice actor and motion capture artist for Casey in their video game Grand Theft Auto V (2013).
Director Dan Pritzker cast him to play real life Chicago mobster Johnny Collins (Louis Armstrong's music manager) in the film Bolden! (release TBD).
In 2014, Wincott made his directorial debut with the dark comedy short film Behind Bars about struggling with addiction.
