He has been winning tournaments in Canada and North America since the late-1960s. He won the 1969 U.S. Junior Open. His biggest paycheck was for topping the field at the 1980 World Open. Day won three Canadian Open Chess Championships (1976, 1980, 1988). He won the Quebec Open Chess Championship three times (1974, 1975, 1979). He won the 1991 Closed Canadian Chess Championship. He tied for first place at the 1999 North Bay International Open, the last of that series of six annual excellent tournaments held there. So far he has won the Toronto City Championship Cup five times (1977, 1980, 1983, 1984, 1995). Day has won several dozen weekend Swiss format tournaments in Ontario since the late 1960s.