CO 4Bet

Overview

The CO 4Bet refers to a fourth raise (4-bet) executed from the cutoff (CO) position in poker. The cutoff is the seat directly to the right of the dealer button, considered a late position with significant strategic advantages. A 4-bet is typically a re-raise of a 3-bet, indicating a strong hand or a polarized range designed to force folds or build a pot while in position.

Strategic Context

In modern no-limit hold'em, 3-betting and 4-betting are common preflop maneuvers. The CO 4Bet is particularly powerful because the player acts after the original raiser (often in early or middle position) but before the button and blinds. Being in position postflop allows the CO to control the hand more effectively, making a 4-bet from this seat more attractive than from earlier positions.

When to Use CO 4Bet

• Value: When holding premium hands like AA, KK, QQ, or AK, a CO 4-Bet aims to build a large pot while in position. Opponents may call or re-raise, but the CO will have the advantage of acting last postflop.
• Bluff: Polarized ranges include bluffs like suited aces (e.g., A5s) or low pocket pairs (e.g., 55) that block opponent's value ranges. The goal is to make opponents fold weak 3-bets or marginal hands.
• Defense: Against aggressive 3-bettors, a controlled 4-bet from CO can discourage frequent 3-betting, especially if the CO's opening range is wide.

Typical Sizing

CO 4-bet sizing is usually 2.2 to 2.5 times the size of the 3-bet, adjusted for stack depth. For example, if the CO opens to 3 big blinds (bb), a late-position 3-bet to 9 bb, the CO 4-bet would be around 20-22 bb. This sizing ensures opponents are priced out of calling with weak hands while preserving fold equity.

Considerations

• Positional Advantage: The CO can 4-bet with a wider range than early positions because of postflop position. However, players in the blinds or on the button may still 5-bet (all-in or large raise) with strong holdings.
• Stack Sizes: Effective stacks significantly affect 4-bet strategy. With deep stacks (100+ bb), 4-bets are more common and can be larger; with short stacks, 4-bets often commit to all-in and become simpler value or shove decisions.
• Opponent Tendencies: Against tight 3-bettors, the CO should 4-bet less frequently; against loose 3-bettors, a wider 4-betting range (including bluffs) is profitable.

Example Hand

Scenario: 6-max, effective stacks 100 bb. CO opens to 3 bb with A♠K♦. Button 3-bets to 9 bb. CO 4-bets to 22 bb. The button folds, and the CO wins the pot. This illustrates a standard value 4-bet; if the button calls, the CO will be in position on a favorable flop.

Related Terms

• 3-Bet: The initial re-raise preflop, often from late position or the blinds.
• 5-Bet: The re-raise of a 4-bet, typically indicating a very strong hand or maniacal aggression.
• Cutoff (CO): The seat one to the right of the button; strategically important for stealing blinds and controlling action.
• In Position: Acting after opponents, providing information advantage.
• Polarized Range: A range consisting of very strong hands and weak bluffs, with few medium-strength hands.