TL;DR: The possibility that Larian will increase the party size to six is next to zero, because the game is turn-based.

  • "Baldur's Gate 3" is a turn-based game, which means combat is slooooooooow. If the party size were increased, then encounters would need to be balanced out as well. I know some of you love slow and unrealistic combat, that emulates tabletop D&D instead of simulating real time combat as D&D itself actually does, but I think that temporally and drastically overemphasized combat encounters would be too much for even the most dedicated turn-based purist to swallow.
  • Larian obviously wants to release this game on console as well. Turn-based combat takes forever on a PC and would take even longer on a console. A larger party size would make Larian's turn-based CRPGs even more unpopular on console than they already are.
  • Gamers would have to spend even more time sorting their inventory, equipping their party, etc. Adding that onto the severe temporal increase of combat encounters would be like adding insult to injury.
  • Probably most importantly, "Baldur's Gate 3" is a D:OS 2 clone. Larian wants to play it safe while reskinning D:OS 2 and will change nearly next to nothing (other than rule set and setting, of course).

I know Baldur's Gate fans wanted a proper sequel and consequently also a party size of six, but sorry, you're not getting it.