The 1972–73 NHL season was the 56th season of the National Hockey League. Sixteen teams each played 78 games. For the first time since the collapse of the Western Hockey League in 1926, the National Hockey League had serious competition. A new professional hockey league, the World Hockey Association, made its season debut with 12 new teams, many of which were based in the same cities as NHL teams. Unlike the Western Hockey League, though, the new World Hockey Association would not challenge for the Stanley Cup. In response to the new league, the NHL hastily added two new teams in an unplanned expansion, the New York Islanders and Atlanta Flames, in an attempt to exclude the WHA from newly constructed arenas in those markets. The first thing the WHA did was sign Bobby Hull, and the Chicago Black Hawks sued, claiming a violation of the reserve clause in NHL contracts. Others soon followed Hull to the WHA, including Bernie Parent, J.C. Tremblay, Ted Green, Gerry Cheevers and Johnny McKenzie. In the expansion draft, the New York Islanders and Atlanta Flames made their picks and eleven Islander players skipped off to the WHA. The California Golden Seals, chafing under the unorthodox ownership of the unpopular Charlie Finley, were also a victim of the WHA, losing eight key players.
Note: GP = Games played, W = Wins, L = Losses, T = Ties, Pts = Points, GF = Goals for, GA = Goals against, PIM = Penalties in minutes Note: Teams that qualified for the playoffs are highlighted in bold