Phil Monckton debuted for the Canadian national rowing team at the 1975 World Championships, where he finished eighth in the coxed eights alongside Joel Finlay, Dirk Gidney, Ian Gordon, James Henniger, Brian Love, and the non-Olympians John Cordonier, Patrick Crosskery, and Fraser Mackay. He was moved to the coxless fours for the 1976 Summer Olympics, where he placed fifth with Gordon, Brian Dick, and Andrew van Ruyven. They had the same result at the 1977 World Championships before Monckton switched to the single sculls and won a silver medal at the 1979 Pan American Games. He was then eliminated in the repêchage of that event at that year’s World Championships.
After Canada boycotted the 1980 Summer Olympics, Monckton surfaced again at the 1983 World Championships, this time as a member of a quadruple sculls crew, and placed fourth alongside Doug Hamilton, Mike Hughes, and Bruce Ford. This quartet saw more success at the 1984 Summer Olympics, where they won a bronze medal, and Monckton retired from active competition shortly thereafter. A graduate of the University of Western Ontario, he has served as the Vice President of High Performance for Rowing Canada since 2004.