The star's publicist confirmed the reports of his passing to IPRESSTV. Mahoney's longtime manager, Paul Martino, said on Monday that Mahoney died after a brief hospitalization. The cause of death was not immediately announced.
Mahoney, who starred as Martin Crane on the hit NBC sitcom for more than 10 years, reportedly passed away in hospice care, according to his publicist.
Born in England in June 1940, Mahoney most recently appeared in an episode of British television drama "Foyle's War" in 2015, and joined the cast of TV Land's "Hot in Cleveland" from 2011 until 2014.
Before his more than 30 years in the entertainment industry, the two-time Golden Globe nominee moved to the U.S. after World War II. He told the Chicago Tribune "It was so bleak and dark in England" and "so sunny" in America.
He served in the U.S. Army for three years before becoming a U.S. citizen and receiving a bachelor's degree from Quincy College in Illinois.
In 1986, Mahoney won a Tony Award for best featured actor in a play for his work in "The House of Blue Leaves," and in 2000 won a Screen Actors Guild award for performance by an ensemble in a comedy series for his work on "Frasier."