6 max to 8-9 handed. How to adjust ranges

1.UTG,
2.UTG1,
3.UTG2,
4.EP (UTG 6max),
5.MP (HJ),
6.CO,
7.BU,
8.SB,
9.BB

JohnnyJam's seat list is the skeleton, so here is the range half. Think of a 9-handed table as your 6-max table with three extra seats bolted on in front. The last six seats play basically your 6-max ranges: the seat he labels EP is your 6-max UTG, MP there is your HJ, then CO, button and blinds unchanged. The three new seats, UTG through UTG+2, need genuinely tighter ranges than anything you use at 6-max, because you are opening into eight players instead of five. That is the whole logic: players left to act sets the range, which is why UTG plays tight and the button plays widest at any table size.

So nothing about your late-seat game changes. You are adding three early seats where you fold most hands, and actually doing that folding is the entire adjustment. A rough anchor, not gospel: full-ring UTG opens something like half of your 6-max UTG range, then you widen seat by seat until the ranges meet at the seat six off the button.

This is true to a good approximation. There is another effect, though that makes, for instance, playing the button at a 6-max table not exactly equivalent to playing the button at a 9-max. That is card removal. If there are more players who have folded before you act, then it’s more likely those players did NOT have high cards, and hence it’s more likely the blinds will have a good hand. In 9-max, therefore, you would theoretically play a slightly tighter button range than you would at 6-max. But if you just played the same ranges it wouldn’t be a huge error.