Scott was born in Lincoln, Nebraska and was raised in Albuquerque, New Mexico as a Seventh-Day Adventist, whose doctrine virtually prohibited movies. Scott studied art history at New College of Florida in Sarasota.
Moving to Canada in 1969 as a draft evader, he settled in Calgary and began writing film reviews for the Calgary Albertan a few years later. He won a National Newspaper Award in 1975, and moved to Toronto when he was hired by The Globe and Mail in 1977.
With the Globe and Mail, Scott became Canada's most influential film critic, winning two more National Newspaper Awards for his writing, and is still widely remembered as one of the best and most influential film critics in the history of Canadian journalism. He was also the host of Jay Scott's Film International, a film series on TVOntario, and published three non-fiction books on both film and art: Midnight Matinees, Changing Woman: The Life and Art of Helen Hardin, and The Prints of Christopher Pratt.
From 1967 to 1980, he was in a relationship with Mary Bloom, whom he had met while studying in Sarasota. After his divorce from Bloom, he came out as gay and began a relationship with Gene Corboy.
He died of AIDS-related causes in 1993. He wrote for the Globe and Mail until his death, and had been working on a book about Norman Jewison. On the night of his death, TVOntario pulled a scheduled rerun of Film International to broadcast a tribute to Scott, including a screening of one of his all-time favorite films, Jean-Luc Godard's Breathless.
Roger Ebert eulogized Scott as a "supremely well-informed critic who was able to translate his knowledge into superb prose that transmitted his passion for the movies." Clint Eastwood sent an unsolicited $5,000 donation to Toronto's Casey House AIDS hospice in Scott's memory. At the 1993 Toronto International Film Festival, filmmaker John Greyson dedicated his Special Jury Citation for Zero Patience to Scott's memory.
A collection of his reviews, Great Scott! The Best of Jay Scott's Movie Reviews, was published posthumously in 1994; proceeds from the book sales were donated to the Canadian Foundation for AIDS Research.
- "Critic Jay Scott, 43 among world's best". Toronto Star, July 31, 1993.
- Leonard Klady (2 August 1993). "Jay Scott [obituary]". Variety. Retrieved 15 January 2016.
- "Globe's Jay Scott dies suddenly at 43: A rare film critic respected by all". The Globe and Mail, July 31, 1993.
- "O Critic, Where Art Thou?", Ryerson Review of Journalism, 2002.
- "Critic Scott eulogized as `secular saint'". Edmonton Journal, August 5, 1993.
- "Eastwood donates to hospice in film critic's memory". Ottawa Citizen, August 20, 1993.
- "Critic Jay Scott is not forgotten as Canadian and foreign film-makers pick up their awards at the Festival of Festivals". Ottawa Citizen, September 20, 1993.
- "Critic's great voice lives on in collection". Ottawa Citizen, October 9, 1994.
- "New award named for Jay Scott". The Globe and Mail. December 4, 2009. Retrieved January 15, 2016.