Here's a look at where each franchise stands as well as some of their closest calls:
The longest title drought in North American sports belongs to the Chicago Cubs, who last won in 1908. After decades of near-misses and superstitious setbacks, the Cubs are World Series favorites heading into the NLCS (Game 1 is Saturday on FS1, 8 p.m. ET/7 p.m. CT). Chicago returned to the World Series seven times from 1910-45, but hasn't been back since.
Closest call: In their last trip to the World Series, in 1945, Chicago pushed the Tigers to seven games. Most recently, the Cubs were four victories shy of a return, but were ultimately swept by the Mets in the NLCS a year ago. Chicago also infamously brushed with a Fall Classic appearance in 2003, squandering a 3-2 lead in which they were five outs from advancing in Game 6.
If not for the Cubs, the Indians, who begin the ALCS against the Blue Jays on Friday (8 p.m. ET on TBS/Sportsnet) would own the longest title drought in baseball. Cleveland last won the World Series in 1948, beating the Boston Braves in six games. After that championship, the Tribe returned to the World Series in 1954, losing to the New York Giants, but didn't make the playoffs again until 1995. They've made the playoffs nine times since.
Closest call: The Indians ended their 40-plus year postseason absence in 1995 by returning to the World Series and pushing the Braves to six games. The Tribe got as far as Game 7 of the Fall Classic in 1997, but the Marlins rallied and won in extra innings.
The Dodgers, who take on the Nationals in Game 5 of the NLDS on Thursday (8 p.m. ET, FS1), have reached the playoffs seven times since the turn of the century but don't have a title to show for it. Their last World Series win was against the A's in 1988 featuring Kirk Gibson's iconic pinch-hit, walk-off home run in Game 1.
Closest call: Los Angeles was two wins from the Fall Classic in 2013, the beginning of four consecutive playoff appearances. The Dodgers fell to the Cardinals, 4-2, in the NLCS as St. Louis beat Clayton Kershaw twice.
The Blue Jays may be the most recent World Series victor of this bunch, but it's still been more than 20 years since fans in Toronto have celebrated a championship. The Jays won back-to-back titles in 1992-93, beating the Braves and Phillies. They've made the playoffs just twice since, advancing to the AL Championship Series this year and last.
Closest call: The Blue Jays overcame tremendous odds last year, becoming just the third team to ever battle back from losing the first two games of a five-game playoff series at home to beat the Rangers in the AL Division Series. Toronto then took two games from the Royals in the ALCS, pushing the eventual champions to six games.
The Nationals, along with the Mariners, are one of two current Major League clubs that haven't appeared in a World Series. Since the team moved to Washington in 2005, the Nationals have not advanced past the NLDS in '12 vs. the Cardinals and in '14 vs. the Giants.
Closest call: The franchise's postseason history includes three trips to the NLDS, all in the past five years, and one NLCS appearance in 1981. The Expos lost to the eventual-champion Dodgers in five games that year.