Position doesn\'t just decide which hands to open — it decides how to play them. Early-position players (UTG, MP) should open slightly bigger (2.5-3bb) since many players remain behind who could join. Late-position players (CO, BTN) can open smaller (2-2.3bb) since fewer players remain. Postflop, the IP player controls pot size: small bets for cheap information, big bets when the hand is strong and the opponent is unlikely to fold easily. The OOP player must decide everything upfront — check-raise, donk-bet, or check-call — without knowing what the opponent will do.
3-bet ranges are also position-dependent: a 3-bet from SB or BB against a BTN open can be relatively wide because the button's opening range itself is wide. Against a UTG open, a 3-bet must be much tighter since the range facing you is already strong. See our 3-Bet in Poker guide for more.