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BB Defence vs Cutoff Open (6-Max)

Against a cutoff open you defend about 42% of hands from the big blind — 3-bet roughly 6% (TT+, AJs+, KQs, A5s–A4s, AQo+) and call about 36%. Tighter than against the button (53%), because the cutoff opens 29% instead of 43%.

Chart

AAAKsAQsAJsATsA9sA8sA7sA6sA5sA4sA3sA2s
AKoKKKQsKJsKTsK9sK8sK7sK6sK5sK4sK3sK2s
AQoKQoQQQJsQTsQ9sQ8sQ7sQ6sQ5sQ4sQ3sQ2s
AJoKJoQJoJJJTsJ9sJ8sJ7sJ6sJ5sJ4sJ3sJ2s
AToKToQToJToTTT9sT8sT7sT6sT5sT4sT3sT2s
A9oK9oQ9oJ9oT9o9998s97s96s95s94s93s92s
A8oK8oQ8oJ8oT8o98o8887s86s85s84s83s82s
A7oK7oQ7oJ7oT7o97o87o7776s75s74s73s72s
A6oK6oQ6oJ6oT6o96o86o76o6665s64s63s62s
A5oK5oQ5oJ5oT5o95o85o75o65o5554s53s52s
A4oK4oQ4oJ4oT4o94o84o74o64o54o4443s42s
A3oK3oQ3oJ3oT3o93o83o73o63o53o43o3332s
A2oK2oQ2oJ2oT2o92o82o72o62o52o42o32o22

3-betMixedCallFold

3-bet: TT+, AJs+, KQs, A5s-A4s, AQo+
5.9% of hands (78 combos)

Call: 22-99, A6s-ATs, A2s-A3s, K2s-KJs, Q5s-QJs, J7s-JTs, T7s+, 96s+, 85s+, 74s+, 64s+, 53s+, 43s, A2o-AJo, K9o-KQo, Q9o+, J9o+, T9o, 98o
36.2% of hands (480 combos)

The rule that generates every big-blind defending range is simple: defend against strength, not against position. The cutoff opens 29% of hands versus the button's 43%, so the average hand you face is materially stronger. Your price has not changed — still about 27% equity to break even at showdown — but your weakest hands have less raw equity against a 29% range and realise even less of it, so the defending range shrinks from 53% against the button to 42% here.

One thing that does not change: by the time the action reaches you, the button and the small blind have already folded. You close the action — nobody can squeeze behind you — so the tightening comes entirely from the stronger range in front of you, not from fear of a third player. It is the same heads-up, out-of-position pot as against the button, just against better cards.

The 3-betting range narrows accordingly. A5s, A4s stay in as the bluffs (same blocker logic as against the button), but the value portion tightens to TT+, AJs+ and AQo+. KJs and AJo, which are 3-bets against the button, become calls here — they are dominated too often by the cutoff's tighter opening range.

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BB Defence vs Cutoff Open (6-Max) — 13×13 poker range chart, colour-coded by action
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FAQ

How much should I defend from the big blind against a cutoff open?

About 42% in 6-max — roughly 6% as a 3-bet (TT+, AJs+, KQs, A5s–A4s, AQo+) and 36% as a call. That is narrower than your defence against a button open (53%), because the cutoff's opening range is narrower too (29% against 43%).

Why do I defend less against the CO than against the BTN?

Because the cutoff opens a stronger range (29% versus the button's 43%), so your marginal hands have less equity against it and realise less of what they have. It is not about anyone behind you: the button and small blind have already folded and you close the action, so the opener's range is the whole reason to tighten up.

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Related charts

BB Defence vs Button Open (6-Max)BB Defence vs UTG Open (6-Max)UTG Opening Range (6-Max)8bb Push/Fold Chart (9-Max Nash)

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Cash-game ranges are a curated GTO reference, drilled question-by-question in the trainer. The mixed band lists hands solvers play only part of the time; we do not have exact frequencies for it, so the percentages on this page count the core range and the core-plus-mixed width separately.

Updated 2026-10-22

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