The five Major League Baseball teams that have never won a World Series are:
- Seattle Mariners
- Colorado Rockies
- Milwaukee Brewers
- San Diego Padres
- Tampa Bay Rays
Among these, the Seattle Mariners stand out as the only team that has never even appeared in a World Series. The others have appeared but have not secured a championship title. The Tampa Bay Rays and San Diego Padres have each appeared twice in the World Series but lost on both occasions, while the Rockies and Brewers have appeared once each without winning.