The Boston Celtics have been the winningest NBA franchise championship-wise for over 50 years. The Lakers could claim to be the team with the best winning percentage for a long time, though. With L.A. struggling in recent years and San Antonio winning big on a regular basis, that’s no longer the case… The Spurs are now the owners of the top winning percentage and look to expand their advantage as the Lakers continue their rebuilding process.
As of 2016, the Phoenix Suns are the winningest NBA team without a championship. The Wizards, 20 spots behind the Suns in the ranking, have one.