Knowing how to play with different stack sizes in tournaments is extremely important to becoming a winner in this modality. By paying attention to your stack and that of your opponents, you will be able to make more efficient plays, and therefore, win more.
Stacks of 10BB or less
Every play you make should be all-in. You will either be starting the play with a shove (all-in), or folding. Note that if you are going all-in against a player who raised, if he has 15BB or less he will rarely fold, so your fold equity will be 0 or close to it. If your opponent on the other hand has a lot of chips, he will also tend to call, knowing that the call represents only a small part of the stack. It is best to shove against players with medium stacks like 15~25BB. It is also good to know that the smaller your stack, the less fold equity you will have. Someone going all-in with 4BB will get much more calls than someone going all-in with 10BB.
10~15BB
When there are antes in play, stacks become shallower, and so it is correct to go all-in with up to 15BB preflop. If there are no antes, you should only raise with strong hands so that you can call all-in re-raises from your opponents. If you do not have strong hands, prefer to save your stack so that you will be more efficient when you decide to go all-in or re-steal someone who is trying to steal the blinds. The only exception is if you are in late position at the table and there are tight players in the blinds, who will not re-steal very often.
15-22BB
This is the smallest stack you can consider raising/folding with. You should generally raise/call with this stack. Of course, you can sometimes raise/fold against tighter, less aggressive opponents who won't re-steal as much and will likely have strong hands. In general, raise/calling is the best play.
Starting with 15BB, this is a good stack size to gain more fold equity with your all-ins, so it's a good stack to re-steal with semi-bluff hands that have good equity against your opponent's calling range. You want situations where:
Your opponents' raising range is wider and they are more likely to fold if you shove high. Additionally, if you have a tight image and a hand that has decent equity against the calling range (suited connectors, suited broadways, suited pairs and aces), then this will be a good spot to re-steal all-in as a semi-bluff and should be profitable. When you get called you will still have something like 30%+ equity against Villain's range. This is a profitable play because your opponent will generally fold enough times to justify the negative equity of the times we get called.
22-35BB
With this stack you have more room to maneuver and can afford to raise with more hands and try to steal blinds and antes more often. Other people may notice this so be prepared to get re-stealed all-in or with a wider range when playing against short stacks. If you are at a table with a lot of players who will go all-in on your raise then you need to adjust by raising fewer hands and playing tighter.
It is also not valid to re-steal all-in with a stack of this size, as it is a bit too big. If, for example, you have a hand that is strong enough to want an all-in from a player with a similar stack size to you, it is better to 3-BET 3 to 9 times the BB and go all-in on the flop. The all-in should be approximately the size of the pot or a bit larger, so it is completely acceptable.
35-45BB
The biggest mistake people make with this stack range is 3-betting preflop with the intention of folding to a 4-bet. Any time you put in 8~10 blinds from this stack preflop and then fold to an all-in you are making a costly mistake, especially if your opponent is 4-betting with a wide range. If you are playing against the type of opponent who folds 90% to a 3-bet, and will fold strong hands like TT and JJ preflop then this can be a profitable play, however, for the most part it is not worth 3-betting/folding with this stack.
With this stack you can also think about playing more hands in general. If it is an early game in the tournament it is still better to play tight, but in the antes playing more hands becomes more profitable.
More than 45BB
This stack size allows for great maneuverability. You can 3-BET/Fold, you can 4-BET shove over 3-BETs (with 45BB on a 9BB 3-BET you have great fold equity), and if you are in the middle or late game, chances are you are one of the chip leaders in the tournament and can take advantage of that to win as much as possible. Now congratulations, you just need to keep playing and make it to the final table!
Article translated and adapted from the original: Tournament Short Stack: How To Survive
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