CO 25bb ICM Spot

Understanding the Components

• CO (Cutoff): The position one seat to the right of the button. In 6-max or full-ring games, the cutoff acts directly before the button and after the hijack.
• 25bb (25 big blinds): A moderately short stack in tournaments. At 25bb, the player is not yet desperate but has limited room for maneuver. Standard open-raise sizes are typically 2-2.5bb, meaning a 25bb stack can sustain about 10 open raises without chips lost to blinds.
• ICM (Independent Chip Model): A model that converts tournament chip stacks into equity (dollar value) based on the payout structure. In ICM spots, the value of chips changes non-linearly; losing chips reduces equity more than gaining chips increases it. This creates tighter decision thresholds compared to cash games.

Strategic Implications

When you face a decision in the CO with 25bb under ICM pressure, several factors come into play:

• Open-raising range: Typically, a 25bb stack in the CO can open a wide range (around 30-40% of hands) but must adjust based on ICM. If the bubble is near or pay jumps are steep, tighten the range because losing a showdown against a bigger stack is costly.
• Reaction to raises: When facing a 3-bet, a 25bb stack can either shove, call, or fold. Shoving is common with hands that have good equity against the 3-bettor’s range, but ICM may force you to fold marginal hands that would be profitable in a cash game. For example, AJo might be a standard shove in a cash game but a fold in an ICM spot if the raiser is covering you and the bubble is looming.
• Stealing blinds: Since 25bb is large enough to put pressure on smaller stacks, stealing from later positions (button and blinds) is profitable. However, if the blinds are aggressive defenders, you may need to tighten your stealing range to avoid being forced to fold to 3-bets.

Example Scenario

Suppose you are on the bubble in a 9-max tournament with 10 players remaining and 9 paid. You have 25bb in the CO, and others have varied stacks (40bb, 20bb, 15bb, etc.). You are dealt KTs. In a cash game, this is a standard open. Under ICM, you might fold because (a) the chip-up to the next pay jump is small, and (b) a confrontation with a bigger stack could risk elimination. This is a typical tight adjustment.

Conclusion

Mastering CO 25bb ICM spots requires understanding that chip preservation often outweighs chip accumulation. Adjust opening ranges, raise sizes, and response to 3-bets based on tournament stage, stack distribution, and payout jumps.