Grant Macdonald was born in Montréal in 1909. He received private lessons from artist Carl Ahrens. During his adolescence he went to Toronto where he was hired to create art work for a city newspaper. In the evenings he attended the Ontario College of Art.
In 1930, Macdonald traveled to England and Europe. In London he did sketches for The Daily Telegraph, The Morning Post, The Sketch, The Bystander and other London publications. Often his sketches were theatrical portraits, celebrity and political portraits. While in London he attended Heatherley's Art School in 1933.
In New York he managed several sessions at the Art Students' League between 1930 and 1940, under George Bridgman, Robert Brackman and Ivan Olinski. His theatrical portraits appeared in The Herald Tribune and the Theatre Arts in New York City and his portraits of actors were used on theatre posters and programmes both in London and New York. In Canada, Macdonald's portraits appeared in the Montreal Gazette, the Toronto Saturday Night, and The Toronto Star.
Macdonald has a solo exhibit at the Roberts Gallery, in Toronto in 1941. In 1943 a series of wartime drawings he created were displayed in a solo show at the Montreal Museum of Fine Arts, then toured Canada. He also completed sketches for The Canadian National Railway which appeared in Canadian National Magazine during 1943 and 1944.
In 1943 he enlisted in the Royal Canadian Naval Volunteer Reserve to record for the Directorate of Special Services. Many of the paintings and drawings he created during this time have were reproduced in Sailors published by MacMillan, Toronto, in 1945.
He continued to create portraits and theatrical paintings and sketches for the remainder of his career.
He was a member of The Royal Canadian Academy (A.R.C.A. 1954, R.C.A. 1967); Ontario Society of Artists (1950); Art Collection Society of Kingston (1958).
His work is part of the collections at The Art Gallery of Ontario, Toronto, Agnes Etherington Art Centre, Queen's University, Kingston, The Art Collection Society of Kingston, The Hart House, University of Toronto, among others.
He died in 1987.