Poker 4-Bet Strategy: Sizing, Hands & When to 4-Bet
Last updated: May 11, 2026
A 4-bet in poker is the fourth bet in a preflop betting sequence — a re-raise of the 3-bet. In Texas Hold'em, the sequence runs: open raise (2-bet) → 3-bet → 4-bet → 5-bet (all-in). A 4-bet almost always signals a very strong hand or a well-timed bluff, and it forces the 3-bettor to commit or fold. Standard 4-bet sizing is 2.2–2.5× the 3-bet when in position, and 2.5–2.8× when out of position. Value 4-bets are built around AA and KK, which should almost always be 4-bet, with QQ and AKs added in most spots depending on position and opponent tendencies. Optimal 4-bet bluffs use suited wheel aces (A5s, A4s, A3s) because they block AA combinations while retaining equity if called. This page covers when to 4-bet, which hands to use, correct sizing by position, how to respond to a 4-bet, and the most common mistakes.
What Is a 4-Bet in Poker?
The name comes from counting the bets in the preflop sequence. The big blind post is the first forced bet. An open raise is the second bet (2-bet). A re-raise of that open is the 3-bet. A re-raise of the 3-bet is the 4-bet. If the action continues, a 5-bet is almost always all-in at 100bb stack depths.
4-bets are rare — they occur in roughly 2–4% of hands in a typical cash game. Because of their rarity and the pot sizes involved, a 4-bet almost always means one of two things: an extremely strong holding (AA, KK) or a calculated bluff with a hand chosen specifically for its blocker value. Random or undisciplined 4-bets are exploitable and should be avoided.
1st Bet
Big blind post (forced)
2nd Bet (Open)
Raise from any position
3rd Bet (3-Bet)
Re-raise of the open
4th Bet (4-Bet)
Re-raise of the 3-bet
5th Bet (5-Bet)
All-in at most depths
4-Bet Sizing: IP vs OOP
Out-of-position 4-bets require larger sizing to compensate for the positional disadvantage you will face post-flop if called. A bigger size forces the 3-bettor to call more chips relative to the pot, reduces their realized equity, and increases the fold rate against marginal holdings.
Example: BTN opens to 2.5bb, CO 3-bets to 9bb. If BTN is in position, a 4-bet to 20–22bb (2.2–2.5× the 9bb 3-bet) is standard. If the SB faces the same 9bb 3-bet, the OOP 4-bet should be 23–25bb (2.5–2.8×). The extra size denies the caller a profitable in-position call with speculative hands.
Value Hands for 4-Betting
Value 4-bets aim to build the largest possible pot with the strongest hands. AA and KK are virtually always 4-bet — they are so far ahead of the 3-bettor's range that slowplaying (just calling) is an error that loses value. QQ and AKs are strong 4-bets in most positions but can occasionally call against very tight 4-bet ranges in deep stacks. JJ and AKo are the borderline hands: they become 4-bets or calls based on position, stack depth, and how wide the opponent's 3-betting frequency is.
Always 4-Bet
AA, KK
Too strong to flat. Want to play for stacks. Slowplaying vs a 3-bet is almost always a mistake.
Usually 4-Bet
QQ, AKs
Strong enough to build a large pot. Avoids multiway pots where equity is diluted.
Situational
JJ, AKo
Depends on position and opponent 3-bet frequency. Can call vs tight ranges; 4-bet vs wide aggressive 3-bettors.
4-Bet Bluffing with Suited Aces
The ideal 4-bet bluff does two things simultaneously: it blocks the strongest hands in your opponent's range, and it retains equity when called. Suited wheel aces — A5s, A4s, A3s — satisfy both criteria better than almost any other hand.
When you hold an ace, you remove one of the four aces from the deck. A full set of AA combinations is 6 (C(4,2)). Holding one ace drops that to 3 combinations — cutting the opponent's most likely 4-bet calling hand in half. Against a typical 4-bet calling range (QQ+, AKs), a hand like A5s retains approximately 40% equity, making calls manageable.
A5s
Blocks AA (3 combos instead of 6). Retains equity vs QQ/AKs. Can make the nut flush and wheel straight.
A4s
Same blocker value as A5s. Slightly less straight equity but identical logic against the top of opponent's range.
A3s
Strong blocker + nut-flush potential. The 3 gives a wheel draw (A-2-3-4-5) and the ace dominates AK combinations.
Hands to avoid bluff 4-betting: KJs, QJs, T9s. These have too much equity and playability to fold pre-flop, but they are crushed if called by a tight 4-bet calling range. Their blocker value is also weaker — they do not block Aces directly.
Hand Selection for 4-Betting
How to Respond to a 4-Bet
Facing a 4-bet, your default posture should be tight. A 4-bet pot commits a large portion of your stack, and the 4-bettor's range is heavily weighted toward AA and KK. The pot odds of calling a 4-bet are around 25–30%, meaning you need roughly that much equity just to break even on the call — and post-flop you will often be out of position and dominated.
Decision framework: AA and KK always 5-bet. QQ and AKs usually 5-bet and occasionally call in deep-stacked spots. JJ and AQs typically call or fold — 5-betting these as bluffs is rarely correct. All 3-bet bluffs (A5s, suited connectors) should fold to a 4-bet.
Common 4-Bet Mistakes
Even strong players make systematic errors around 4-bets. The most costly mistakes:
Slow-playing AA vs a 3-bet
The most common mistake. AA is so strong it should almost always 4-bet. Calling a 3-bet with AA lets in dominated and drawing hands cheaply, and disguises your hand at the cost of leaving value on the table.
4-bet bluffing with the wrong hands
KQs, QJs, and suited connectors have too much realized equity to fold preflop but are crushed when called by the 4-bettor's value range (AA, KK, QQ). They also lack the direct blocker advantage that makes A5s/A4s effective.
Sizing too small out of position
OOP 4-bets that mirror IP sizing (2.2× instead of 2.5–2.8×) give the 3-bettor an easy call in position. The extra size is not optional — it compensates for the post-flop disadvantage.
4-betting into very tight 3-bet ranges
Against players who only 3-bet AA, KK, and QQ, a bluff 4-bet has almost no fold equity. Adjust by calling more hands instead of 4-betting as a bluff, and save aggressive 4-bets for players with wide 3-bet frequencies.
Definitions
Frequently Asked Questions
What is a 4-bet in poker?
A 4-bet is a re-raise of a 3-bet preflop. In the standard betting sequence, the big blind post is the first forced bet, an open raise is the 2-bet, a re-raise is the 3-bet, and a re-raise of that is the 4-bet. A 5-bet usually means all-in. In a 100bb cash game, a standard 4-bet is typically 20–25bb depending on position.
What hands should I 4-bet?
Always 4-bet AA and KK — these hands want to play large pots and build stacks preflop. Add QQ and AKs as standard value 4-bets in most positions. Include some bluffs: A5s, A4s, and A3s are the best because they block Aces in the opponent's range while retaining equity if called.
How big should a 4-bet be?
Standard 4-bet sizing is 2.2–2.5× the 3-bet when in position, and 2.5–2.8× when out of position. If the 3-bet was to 9bb, a typical IP 4-bet would be 20–22bb, and an OOP 4-bet would be 23–25bb. Going larger out of position compensates for the positional disadvantage post-flop.
What is the best 4-bet bluff?
The best 4-bet bluffs are suited wheel aces — A5s, A4s, and A3s. These hands block the Ace-Ace combinations in your opponent's 3-bet range (removing some of their strongest value hands), have reasonable equity when called (~40% vs QQ type ranges), and can make the nut flush if they see a flop.
What should I do when facing a 4-bet?
Fold most hands. 4-bets represent a very strong range. Call with hands that have good equity against that range and play well post-flop (e.g., QQ or AKs in position). 5-bet (all-in) with AA and KK — never slow-play these against a 4-bet. Almost all 3-bet bluffs should be folded to a 4-bet.
What is the difference between a 3-bet and a 4-bet?
A 3-bet is the re-raise of an open raise — the first aggressive escalation preflop. A 4-bet is the re-raise of the 3-bet — the second escalation. Both are part of a betting sequence. 3-bets are more common (typical frequency: 5-10% of hands from LP) and include more bluffs. 4-bets are rarer (~2-4%) and represent a much narrower, stronger range.
Related Guides
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