3-betting and 4-betting in cash games: when to reraise, what size, and how to respond

What a 3-bet is and why it has that name

When you count preflop bets, the big blind is the first bet, the open is the second and the reraise is the third, which is why it is called a 3-bet. A reraise over that 3-bet is a 4-bet, and the next one is a 5-bet.

A 3-bet does two jobs at once:

• Value: with A♥A♦, K♣K♥ or A♠K♦ you want more money in while you are ahead.
• Pressure: with hands that would rather not call or fold, you win the pot without seeing a flop or play a bigger pot with the initiative.

A 3-bet also isolates one opponent. If you flat the open from the CO, the BTN and the blinds can still come in or squeeze; if you reraise, the hand is usually heads-up.

Linear or polarized: which hands to 3-bet

There are two ways to build a 3-bet range:

• Linear (merged): the best hands from the top down, with no gaps. You use it when flatting is not an option, as in the SB, where a call leaves the BB behind and you play out of position.
• Polarized (polarized): strong value plus bluffs, while the middle hands go to the call. You use it when calling is a good option, as on the BTN with guaranteed position.

The POKER AULA preflop charts show it like this:

Against UTG the value range shrinks to QQ+ and AK: the opening range is strong (14% of hands) and a light 3-bet runs into what continues. Against a CO that opens 27%, AJs, KQs and AQo join the value range.

Why A5s is the classic bluff. Your ace is a blocker: it removes combos your opponent continues with. Holding an ace, AA goes from 6 combos to 3 and AK from 16 to 12. And when you get called, A5s still has flush and straight potential.

3-bet sizing in position and out of position

Against a standard 2.5 bb open:

• In position (from HJ, CO or BTN): 7.5 bb, three times the open.
• Out of position (from SB or BB): 11 bb, 4.4 times the open.
• BB vs a 3 bb SB open: 9 bb, because you have position.

You go bigger out of position for two reasons: you charge the opponent more for the positional edge, and you lower the SPR, which shrinks how much that position is worth on later streets.

Sizing also sets how many folds a bluff needs. If you 3-bet to 7.5 bb on the BTN against a 2.5 bb CO open, you risk 7.5 to win 4 bb (the 2.5 open plus 1.5 in blinds). Alpha is 7.5 / (4 + 7.5) = 65.2%. If the opponent folds less than that, a pure bluff loses chips, so you pick bluffs that have equity when called.

Facing a 3-bet: fold, call or 4-bet

You opened 2.5 bb from the CO and the BTN 3-bet to 7.5 bb. The pot holds 11.5 bb and calling costs 5 bb: you need 5 / (11.5 + 5) = 30.3% equity. That looks cheap, but you will be out of position, and dominated hands realize much less equity than they have.

The POKER AULA chart for that spot:

• 4-bet: QQ+, AKs, AKo, with JJ, AQs and KQs mixed, plus A5s or A4s as bluffs.
• Call: 66-TT, ATs-AJs, KJs, KTs, QJs, QTs, JTs, T9s, 98s, AQo.
• Fold: everything else, including offsuit A♥J♦ and K♣Q♦.

If you opened from UTG, the calling range tightens: 88-JJ, AJs-AQs and AKo, with KQs or JTs becoming borderline. Your open was strong, but the BTN 3-bet range against UTG is strong too.

If the 3-bet comes from the BB to 11 bb after your BTN open, calling costs 8.5 bb for a final pot of 22.5: 37.8% equity needed. It is pricier, but you have position, so the chart calls with 22-TT, suited aces, suited connectors and AJo-AQo.

Once you call, the 3-bet pot has a low SPR: in the CO vs BTN example, 92.5 bb remain behind with a 16.5 bb pot, an SPR of 5.6. With a strong top pair you are already thinking about getting stacks in.

4-bets and 5-bets at 100 bb

POKER AULA uses 18 bb against a 7.5 bb 3-bet (2.4 times), 24 bb against an 11 bb 3-bet (2.2 times) and 21 bb against the 9 bb BB 3-bet when you opened from the SB.

A 4-bet bluff is measured with alpha too. The CO 4-bets to 18 over the BTN 7.5 bb 3-bet: it adds 15.5 bb to win an 11.5 bb pot and needs 15.5 / 27 = 57.4% folds. That is why 4-bet bluffs are few and almost always hold an ace: A5s, A4s.

Facing the 4-bet, the BTN sees a 27 bb pot and calls 10.5: it needs 28% equity, but the SPR becomes 2.2 and almost everything is decided on the flop. The chart:

• All-in (5-bet): KK+, AKs, plus QQ or AKo depending on the opponent.
• Call: TT-JJ, AQs, AJs, KQs.

At 100 bb every 5-bet is all-in. A BTN 5-bet bluff over the 18 bb 4-bet risks 92.5 bb to win 27 and needs 77.4% folds, so that range is almost pure value. Whoever faces the shove calls 82 bb for a final pot of 201.5 and needs 40.7% equity against the range shown.

Common micro stakes leaks

1. Min 3-betting. A 5 bb reraise out of position gives the opener a great price to call anything and play in position. Use 11 bb.
2. Flatting from the SB by habit. Against the BTN, the charts play the SB as 3-bet or fold, except small pairs at passive tables.
3. Calling 3-bets with dominated hands. A♥J♦ from UTG against a BTN 3-bet is a fold: against QQ+, AK and AQ it is crushed.
4. 3-bet bluffing players who never fold. If someone calls almost everything, drop the bluffs and widen your value: KQs, AJs and TT earn more as 3-bets.
5. 4-bet bluffing nits. If a player only 3-bets QQ+ and AK, your 4-bet bluff never gets the 57.4% folds it needs, because that player has nothing to fold.
6. Ignoring fold to 3-bet. If someone opens wide and folds 70% to 3-bets, any 7.5 bb bluff profits from folds alone: alpha was 65.2%.

How to practice it

Learn one chart first: BTN vs a CO open, the spot that comes up most. Then add BB vs BTN and the responses to a 3-bet.

At POKER AULA, 3-bets and 4-bets are taught in the Intermediate level (modules on facing opens and responding to 3-bets) and go deeper in Professional with 5-bets and the folds each bluff needs. The Preflop Charts show every spot with its sizing, and in Training you choose fold, call or reraise and get corrected with THE WHY. The 48-hour free trial lets you go through the charts and drill these spots with no card required.