to answer my own question based upon AI on google
For the 2026 MLB season, teams are permitted to carry a taxi squad of up to five players on road trips to serve as immediate replacements, with at least one player required to be a catcher. These players do not accrue major league service time unless activated and offer flexibility for roster adjustments.
Bucs Dugout
Bucs Dugout
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2026 Taxi Squad & Roster Rules Highlights
Squad Size: Teams may carry up to five players from their Triple-A affiliate on road trips.
Catcher Requirement: At least one of the five players must be a catcher, who can act as a bullpen catcher when not playing.
Activation/Service Time: If a taxi squad player is activated, they do not gain MLB service time or pay, except for the daily per diem amount, unless they are formally added to the 26-man roster.
Roster Limits: Active rosters remain at 26 players from Opening Day through August 31, with a maximum of 13 pitchers.
September Expansion: From September 1 through the end of the season, rosters expand to 28 players, with a maximum of 14 pitchers.
Doubleheaders: Teams can add a 27th player for doubleheaders, often drawn from the 40-man roster.
MLB.com
MLB.com
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These rules ensure teams have readily available backups for injuries or illness without needing to make immediate, permanent roster moves.