List of NBA seasons

The National Basketball Association (NBA) is the major professional basketball league in North America. The league was founded in 1946 as the Basketball Association of America (BAA). The league adopted its current name at the start of when it merged with the National Basketball League (NBL). The league currently consists of thirty teams, of which twenty-nine are located in the United States and one in Canada. Each team plays 82 games in the regular season. Eight teams from each of the league's two conferences qualify for the playoffs. The winners of the Conference finals advance to the finals to determine the NBA champions.

The Boston Celtics have had or tied for the best regular season record a record 18 times. They won the Eastern Conference 10 times, while the Los Angeles Lakers won the Western Conference 19 times. The Celtics and Lakers have each won 17 NBA championships, the most in NBA history. The Lakers also have a record 32 Finals appearances. The Celtics and the Lakers had played each other in the Finals for a record 12 times. The Celtics won 9 of their matchups while the Lakers have only won 3.

The best single regular season record was recorded by the Golden State Warriors in the. In that season, the Warriors recorded 73 wins and 9 losses with a winning percentage of .890, surpassing the 72-win 1995–96 Chicago Bulls, though the Bulls went on to win the Eastern Conference and the NBA championship. The 1996 Bulls and the 2016 Warriors are the only teams to win at least 70 games in a single season.

The Eastern champions have won 38 championships while the Western champions have won 34 championships. The defunct Central Division won one championship in 1950. Of the 76 championships, 34 of them were won by the teams who had or tied for the best regular season record. In 10 other occurrences, the teams who had or tied for the best regular season record, lost the Finals. Six teams that had the best regular season record and won the championships in the same season, were named to the list of Top 10 Teams in NBA History announced at the league's 50th anniversary in 1996. The Celtics, the Bulls, the Lakers and the Philadelphia 76ers each had two teams selected, while the Detroit Pistons and the New York Knicks each had one team selected.