Benson was born in Guelph, Ontario. He is the son of Eugene Benson, an English professor and a prolific novelist, playwright and librettist. He later graduated from the University of Western Ontario with a bachelor of science in chemistry and biochemistry, before studying acting at the George Brown College Theater School in Toronto.
His early roles as an actor included theatrical productions of John Palmer's Singapore, Fabrizio Filippo's Waiting for Lewis, William Shakespeare's Love's Labour's Lost and Robin Fulford's Steel Kiss.
In 2000, he appeared in a Molson Canadian commercial as a Canadian office worker who unleashes a torrent of hockey-style violence on an American coworker taunting him with Canadian stereotypes. In 2001, he was cast in a lead role in the television drama series The Associates. In 2002, following the cancellation of The Associates he was cast in the legal drama series Just Cause, which ran for one season.
Benson played the recurring role of Dr. Steven Lars Webber on the soap opera General Hospital from 2004 to 2005, which attracted him considerable attention compared to his previous roles. Since his time on General Hospital, Benson has guest starred in numerous television series, including Cold Case, The Unit, Tornado Valley, and Being Erica. In 2012, Benson starred in the IMAX 3D documentary film Flight of the Butterflies and in French comedy Populaire.
In the 2015, made-for-TV movie, Kept Woman Shaun played an eccentric professor, Simon, who kidnaps his neighbor Jessica, played by Courtney Ford. Also in 2015, Benson starred in the Starz television series The Girlfriend Experience, alongside Riley Keogh.
In 2016 Benson appeared in the Netflix time loop thriller ARQ as Sonny, as well as Season 2 of the series Gangland Undercover as Crowbar. He subsequently appeared in the SyFy series Channel Zero as the town sheriff, Gary Yolen.
In 2013 Benson directed Stop Kiss for the Toronto Fringe Festival. The production had a sold out run which was extended as a result of winning Best of Fringe honours.
In 2014, Benson directed the independent film Barn Wedding, which won the HMV People's Pick For Best Flick award at the 2015 Canadian Film Fest.