[BB] After a brief respite, Benny the Book has returned with another Hold ‘Em lesson for his son. “You, along with every other poker player, love to get away with a bluff. You win a pot that you shouldn’t have won. Maybe you flash your hole cards to show off what you just did (bad idea, by the way, unless you don’t plan to bluff again for a while).”

[BB] “But before you learn the art of the bluff, you should arm yourself with the safer flop and turn semi-bluff.”

[BB] “A seminar isn’t half a ‘nar’;1 a Seminole2 isn’t half a ‘Nole’; but a semi-bluff is exactly what it sounds like, half of a bluff. It’s partly a bluff because you don’t currently have the best hand but are hoping to win the pot by causing your opponents to fold. But it’s partly not a bluff because of your chance of improving to a better hand than your opponents.”

[BB] “The full range goes from total bluff (no pot equity) to mostly bluff to semi-bluff (up to 50% pot equity) to value bet (over 50% pot equity).”

[JJ] “What’s the distinction between a bluff and a semi-bluff?” Joey the Juvenile interrupted.

[BB] “The line between bluff and semi-bluff isn’t officially defined, but let’s say that a bet with anything less than 5 outs (e.g., an inside straight draw) is more bluff than semi-bluff. It’s not actually that important except to know that along the continuum you’re relying on fold equity more on the left and less on the right.”

[BB] “It’s also impossible to know where semi-bluffs end and value bets begin until you’ve seen all the hole cards. But none of us can read our opponents hands well enough that it matters whether you have 49% pot equity or 51%; as long as you know it’s closer to 50% than 20% or 80%, you’re doing great.”

[BB] “The less pot equity you have, the more you want to take down the pot immediately. The more pot equity you have, the more you don’t mind building the pot.”

[BB] “One issue that comes up with in-position semi-bluffs is when should you take the free card and when should you semi-bluff if nobody bets and you’re last to act?”

  • “The more outs you have, the more often you should check, since your pot equity is high but won’t be increased relatively by betting.”
  • “The more opponents you have, the more likely the flop was to hit your opponents’ hands, the more your opponents like to check-raise, and the more your opponents like to slowplay, the more you should check, since your fold equity is lower in each case.”
  • “The larger the pot is relative to your and your opponents’ stacks, the more you should check because you lower your implied odds by betting (i.e., there aren’t enough chips left to pay you off properly when you hit your draw). In the extreme case, never semi-bluff if you or one of your opponents is pot-committed.”
  • “Otherwise, semi-bluffing usually has a higher EV3 than checking.”

“When you are out of position, reduce the frequency of your semi-bluffs since your fold equity is lower (a player who has checked is more likely to fold than a player who hasn’t acted yet).”

“You can also semi-bluff raise in position and semi-bluff check-raise out of position, but these are both riskier plays with less fold equity.”

“Lastly, I’d add that a side benefit of semi-bluffs is that they help balance4 your flop and turn betting ranges. You’d be too easy to read if you always had a good hand when you bet. By adding semi-bluffs to your arsenal, your strong bets for value will get called more often as your opponents learn that you could also be semi-bluffing.”

“How big your semi-bluffs should be is too opponent- and hand-dependent to say with any certainty. Against unobservant opponents, make your semi-bluffs as small as possible while still inducing folds. Against better competition, the closer your semi-bluff sizing matches your value bet sizing, the harder you will be to read. After we talk about bluff sizing, which is simpler because of the lack of pot equity, we’ll return to the math of this subject.”


  1. “Seminar”, “seminate”, and “seminal” all come from the root “semen-” (seed) rather than “semi-” (half).
  2. “Seminole” comes from the Creek Indian Simano, meaning “wild, untamed, runaway”.
  3. See last month’s article on “Expected Value”.
  4. Sorry, that’s a future article that I haven’t written yet.

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