What Is a Fourbet?
A fourbet is a preflop action in poker that occurs when a player re-raises a three-bet. In a typical no-limit hold’em sequence, the action starts with an initial raise (open raise), followed by a three-bet (a re-raise). If the original raiser or another player responds by re-raising again, that new raise is called a fourbet. The term itself is a simple ordinal label — fourbet — but understanding when and why to use it requires a solid grasp of range construction, stack dynamics, position, and opponent tendencies.
Why Fourbet?
There are two core reasons to fourbet: value and leverage. A value fourbet is made with very strong hands that want to get more money into the pot preflop from worse hands or to isolate an opponent. A leverage or bluff fourbet aims to fold out better hands, take the initiative, and take advantage of fold equity. Good players mix both, making some proportion of their fourbets bluffs to balance the range and make their strong hands less exploitable.
Key Considerations
Before deciding to fourbet, consider these variables:
- Position: Being in position (e.g., BTN vs CO) increases the effectiveness of both value and bluff fourbets.
- Stack sizes: Deep stacks change postflop dynamics; short-stacked situations reduce the frequency of speculative fourbets and favor all-in moves.
- Opponent tendencies: Against tight opponents, fourbet bluffs are more effective. Against loose three-bettors, tighten up and value fourbet more.
- Table image and history: Recent hands and perceived ranges will strongly influence fold equity and exploitation opportunities.
Range Construction
Building a fourbet range is about balance. A robust approach mixes strong value hands (JJ+, AK, sometimes AQ+ depending on dynamics) with a selection of bluffs (suited broadways, suited connectors) placed where they can have equity if called. For example, in a common scenario where CO opens and BTN three-bets, the original raiser can fourbet with a polarized range: premium value hands and speculative bluffs that fare well against calling ranges. Alternatively, a linear approach can be used in very aggressive games or against opponents who fold too often, focusing on a tighter value-based range.
Mathematics and Fold Equity
Fourbetting profitability hinges on fold equity and pot odds. If your fourbet gets folds a sufficient percentage of the time, bluff fourbets can be immediately profitable without seeing the flop. Calculate the break-even fold frequency by dividing the amount you want to win by the total pot after your raise. Understanding these ratios helps you determine how often your opponent must fold for the fourbet to be correct as a bluff.
Examples
Example 1 — Value fourbet: You are the button, CO opens to 2.5bb, and BTN three-bets to 7.5bb. You hold AKo. A fourbet to 25-30bb polarizes your range and often gets called by worse Ax or KK/QQ, while isolating the three-bettor. Example 2 — Bluff fourbet: In the same spot, you occasionally fourbet small with KQs or suited connectors to exploit a three-bettor who folds too frequently. Mix these bluffs sparingly to avoid being exploited.
Position and Postflop Play
Being in position postflop is crucial when you include bluffs in your fourbet range. Positional advantage allows you to control pot size, apply pressure, and make informed decisions based on your opponent’s actions. When out of position, prioritize value hands and be prepared to face difficult decisions on later streets if called.
Stack Depth and Tournament vs Cash Game Differences
In tournaments, where effective stacks often vary and ICM considerations come into play, fourbet frequencies should be adjusted. Shorter stack depths reduce the feasibility of speculative fourbets and increase all-in shoves instead. In cash games with deeper stacks, fourbets can be more strategic and include a wider array of bluffs because postflop play and implied odds reward maneuvering. Recognize that tournament dynamics may punish marginal bluffs due to payout structures and bubble pressures.
Common Mistakes
Common fourbetting errors include overusing bluffs against sticky players, failing to polarize the range, and mis-sizing bets. Overly predictable sizes telegraph your hand strength. Additionally, many players neglect to adjust their fourbet strategy when facing opponents who rarely fold or who fourbet shove frequently. Always review hand histories and adapt.
Practical Training and Tools
To improve, study solver outputs and practice with hand range explorers. Tools that simulate preflop equities and exploitative adjustments can illuminate how often to fourbet and which hands to use. Equally important is table work: take notes, observe tendencies, and use small sample experiments (e.g., changing sizing or frequency) to test reactions. Review key hands and ask whether a fourbet created more value or simply led to uncomfortable postflop spots.
Psychology and Table Image
Your image matters. If you are perceived as aggressive, opponents will adjust by calling or fourbetting back more often. Conversely, a tight image can increase fold equity and make bluffs more effective. Use this consciously: mix your frequencies to remain unpredictable and exploit opponents’ tendencies rather than playing mechanically.
Adjustments Against Specific Opponents
Against hyper-aggressive three-bettors, tighten and value fourbet more; let them overcommit. Versus nittier players, increase bluff fourbets to take down pots preflop. Against opponents who fourbet shove frequently, avoid marginal holdings and defend more with hands that have high postflop playability or good shove equity.
Final Thoughts
The fourbet is a powerful preflop weapon that, when used thoughtfully, can increase your win rate substantially. It requires a mix of math, psychology, and adaptable strategy. Aim to balance value and bluff components, adjust to stack sizes and opponent types, and keep your ranges and sizes unpredictable. With deliberate practice and study, your fourbet decisions will become a significant edge in both cash games and tournaments.
Study, review, and adapt — the fourbet is not just a single move but a strategic mindset that rewards those who understand its nuances and integrate it into a broader, well-balanced game plan.