A rangy 6'1" and 175 pound right winger from Toronto, Bill Shill entered the NHL with the Boston Bruins in 1942-43 but spent only part of the season there, the other portion being spent with the Toronto Navy team in the Ontario Hockey Association Senior division.
He spent the 1943-44 season away from hockey and in the military, and the following year his hockey playing was limited to a stint with the Cornwallis Navy team in the Nova Scotia Senior Hockey League. By 1945-46, Shill was back in the big leagues, recording his best NHL season that year with 15 goals and 12 assists. He spent one more partial year with the Bruins before being sent to the Hershey and Buffalo teams in the American Hockey League.
In 1947 Shill joined the Dallas Texans of the United States Hockey League before becoming a member of the Vancouver Canucks in the Pacific Coast Hockey League from 1948 to 1952. It was during the 1949-50 season that he had his best scoring year as a pro, recording 34 goals and 42 assists for 76 points in 69 games. That beat his record of the previous year, when he registered 43 goals and 69 points. In 1951 he was named to the PCHL First All-Star Team.
After his four years in Vancouver, Shill made a brief stop in Ottawa to play with the Senators of the Quebec Senior Hockey League and then moved to Brantford, Ontario, to join the Redmen of the Ontario Hockey Association Senior division. In 1952-53, he had another excellent scoring year with 36 goals and 27 assists. The following season he landed a job with the Toronto Lyndhursts of the city's senior league as a coach, not competing anywhere as a player.
However, Shill did represent Canada in the World Championship in 1954 as a member of the East York Lyndhursts and scored six goals and three assists for nine points in only seven tournament games. For that effort he was named to the first All-Star team for the tournament, though Canada eventually lost to the Soviets and had to settle for the silver medal.