There's nothing quite like postseason baseball.
The drama. The crowds. The stakes. It's just different.
Postseason rosters and the rules that govern them are a little different than what we see in the regular season as well. So before the 2026 playoffs begin on Sept. 29, here is a quick overview of MLB's postseason roster rules.
How many players are on a team's postseason roster?
Each team carries a 26-player roster into a postseason series. That roster of eligible players must be submitted before the start of each series and can be changed before the start of each subsequent series.
Which players are eligible to be on a postseason roster?
All players who were on a club's 40-man roster prior to Sept. 1 are eligible for postseason play. Same goes for all players who were on the 60-day injured list entering September. Any player who meets one of those two conditions is postseason eligible. That's how a handful of players have made their MLB debut during the postseason.
However, there are a couple of exceptions that are important to note.
Can players who don't meet either of the two above conditions be added to a postseason roster?
Yes. Even players who weren't on a club's 40-man roster or the 60-day IL entering September can make their way into postseason play via a petition to the commissioner's office. However, that player must have been in the organization on Aug. 31 and replacing an injured player who has served the minimum amount of time required for activation.
In other words, any player who has been on the 10-day injured list for at least 10 days or the 60-day IL for at least 60 days can be replaced for a postseason series by any other player who was in the organization before Sept. 1, even if that player wasn't a part of the 40-man roster or on the 60-day injured list entering that month.
Players who were on the restricted list as of Sept. 1 are also eligible to play in the postseason as long as they haven't been suspended for performance-enhancing drugs during the year.
What happens if a postseason-eligible player gets injured during a series?
In the event of a player injury, a club may request permission from the commissioner's office to replace said player during the course of a series, but that player is ineligible to play for the rest of that round and the subsequent round, if there is one.
A pitcher must be replaced by another pitcher, and a position player must be replaced by another position player.
Which players are ineligible for a postseason roster?
There are a couple categories of players who, under no circumstances, can be eligible for a team's postseason roster:
- Any player who joined the organization after Aug. 31. So, any player who was signed or claimed off waivers in September can't be on any postseason roster.
- Any player who was suspended during the year for PEDs.