3-Betting Strategy: Ranges, Sizing and When to Bluff

A 3-bet is the second raise in a betting round, and it earns money two ways: value from hands that beat the opener's continuing range, and fold equity from hands that do not. Everything in between belongs in your calling range or the muck. Get the range construction, the sizing and the bluff selection right and preflop reraising becomes the most profitable aggressive action available to you.

Why 3-betting beats flat-calling

Flatting an open keeps every player behind you in the hand. Call a CO raise on the BTN with A♠J♠ and both blinds get a cheap look, so the pot you helped build is multiway and your hand has to fend off three ranges instead of one.

A 3-bet does three things at once. It folds out the players behind, it isolates the opener while you hold the stronger range, and it takes the betting initiative that pays you on every later street when neither of you connects.

The arithmetic is friendlier than it feels. A 3-bet to 7.5bb over a 2.5bb open risks 7.5bb to win the 4bb already out there, so as a pure bluff it needs to work about 65% of the time. Your bluffs are never pure — they flop pairs, draws and backdoors — so the real break-even fold frequency sits well below that. Add the pots you win with a continuation bet after being called, and the bar drops further still. If the mechanics are still fuzzy, what a 3-bet is covers the definition in thirty seconds.

Linear against wide opens, polarised against tight ones

A linear range 3-bets from the top down and skips nothing: your best hands, then the next best, in an unbroken block. A polarised range 3-bets the very best hands and a selected group of weak ones, while everything in the middle flats.

Two factors decide which shape you use.

• How wide the opener is. The BTN opens roughly 40-45% of hands in 6-max. KQo and 99 are comfortably ahead of that, so raising them for value beats calling. UTG opens roughly 15-17%, a range those same hands are behind — flat them and polarise instead.
• Whether you have position. Out of position you realise less of your equity, so hands that only win by flopping well perform badly as calls. Shifting them into your raising range converts a leaky flat into a hand with two ways to win.

That is the whole reason blind defence looks so raise-heavy: from the SB especially, calling is a losing proposition against most opens, so the range compresses into raise-or-fold. The BB is the exception, because the big blind already invested buys a price good enough to defend a wide flatting range alongside the raises. The full mechanics of each shape, including when to mix, are in polarized and linear ranges.

Building the range seat by seat

Range construction is a matter of pairing a value region with a bluff region that has blockers. A workable starting framework:

Your seat	Facing	Value 3-bets	Bluff 3-bets
BTN	CO open	TT+, AQs+, AK	A5s-A2s, K9s, 76s
CO	UTG open	QQ+, AKs, AK	A5s, A4s, KJs
SB	BTN open	99+, AJs+, AQo+	A5s-A2s, KTs, QTs
BB	BTN open	88+, ATs+, KQs, AJo+	A5s-A2s, K9s, J9s

Notice how the BB row is close to linear and the CO row is sharply polarised. That is not stylistic preference, it is a direct consequence of the opener's width.

Ranges shift with rake, stack depth and how the table actually plays, which is why one memorised grid never survives contact with a real game. The solver-built preflop ranges give you the full grid for every seat and every action, and the cutoff opening range is worth learning first because it is the range you face most often with position on the opener.

Sizing: bigger out of position

In position, 3-bet to about 3x the open. Out of position, 3-bet to about 4x, plus one big blind for every cold-caller already in the pot.

Sizing is not about hand strength, it is about geometry. Out of position you will check first on every street and you will be denied free cards, so you need the opener to fold more often and to pay a worse price when they do not. A larger raise also sets up a stack-to-pot ratio where one flop bet commits you, which removes the awkward turn decisions that cost out-of-position players the most.

Spot	Open	Your 3-bet	Opener's price to call	Pure bluff must work
BTN vs CO	2.5bb	7.5bb	30%	65%
SB vs BTN	2.5bb	10bb	36%	73%
BB vs BTN	2.5bb	11bb	38%	77%

Read the last two columns together. The bigger out-of-position sizing pushes the opener's required equity from 30% up towards 38%, which folds out the marginal suited hands that would otherwise call and outplay you. It also demands more from your bluffs, which is exactly why out-of-position 3-betting ranges lean linear: you cannot support a wide bluff region that has to work 77% of the time.

Choosing the bluffs

Your value hands pick themselves. The bluffs are where the money is made and lost, and the selection criteria are specific.

• Blockers first. A5s through A2s remove one of the aces from AA, AK and AQ, so the opener holds a continuing hand less often. That single card is worth more than any amount of raw equity.
• Suitedness over connectedness. Suited hands flop flush draws that let you continue barrelling when called. K9s is a better 3-bet bluff than KJo despite being the weaker hand at showdown.
• Leave the good flatting hands alone. 76s and 65s realise their equity beautifully as calls when you have position. Raising them turns a profitable call into a marginal bluff and empties your calling range at the same time.
• Bin the offsuit junk. A hand with no blocker and no suit is not a bluff, it is a donation. If the reason you raised was boredom, fold instead.

The nut-flush backup matters more than players expect. A5s reaches the river as the best hand often enough that your bluff quietly doubles as a thin value hand, which is why it appears in almost every seat's bluff region. It also flops a wheel draw, a pair of aces and a nut flush draw at a rate no offsuit broadway can match, so the hand keeps making money on the flops where your fold equity has already evaporated.

When they 4-bet

Decide your response before you 3-bet, not after the raise lands. A 3-betting range with no plan against a 4-bet either folds far too much or stacks off with hands that are crushed.

Against most opponents your continuing range against a 4-bet is roughly QQ+ and AK, with AK often calling rather than jamming at 100bb. Remember what those confrontations actually look like: AA against KK is about 82/18, and AK against QQ is about 43/57 — a slight dog, not a coin flip, and never a hand to be delighted about getting in.

The bluffs you fold are the ones that did their job and lost. A5s that folds to a 4-bet is still a profitable 3-bet, because the pots it won uncontested and the pots it won postflop pay for the times it gets blown off. What it must not do is call. If you want to fight back, do it deliberately — choosing 4-bet bluffs covers which hands belong in a 5-bet-or-fold region.

The leaks that cost the most

1. 3-betting only premiums. If your reraise always means QQ+, observant opponents fold everything but the nuts and you never get paid. Adding blocker bluffs fixes this in one session.
2. Flat-calling from the SB. Calling out of position with a player still to act behind is the single most expensive habit in low-stakes 6-max. Raise or fold.
3. 3-betting too small out of position. A 3x raise from the BB gives the BTN a price they will happily take, and then you play a bloated pot with no position and no fold equity.
4. Bluffing the same hands every time. If A5s is always a raise and A5o is always a fold, your range is legible. Mix the marginal ones.
5. Ignoring cold-callers. When someone has already flatted the open, your bluffs lose most of their value and your sizing needs to grow. Tighten towards value.

Fix those five and your preflop game improves more than any postflop study will deliver in the same time. The reason is structural: 3-betting decisions repeat every single orbit, and the mistakes compound quietly at 2 to 3bb a pot until they are the largest line item in your results. Work on one seat at a time, drill it until the raise-or-fold choice is instant, then move to the next.