River bluffing

River bluffing is the most exciting moment in poker and at the same time the most underestimated piece of arithmetic. On the river there is no safety net left: your hand no longer improves, so a river bluff only wins if your opponent folds. That is why you do not bluff on feel here, but along a fixed checklist. Five questions, and only when all five fall right does the money go in. The checklist below runs through them one by one, in the order you ask them at the table.

Question 1: does your story hold up?

Every bet tells a story, and on the river your opponent reads the whole book back. A credible bluff acts as if you have a strong hand that would have been played this way: raised before the flop, continued on the flop and turn, and now the logical final bet. If you checked two streets and suddenly fire big on the river, something does not add up, and even weak players sense that unerringly. If you cannot think of a strong hand that took exactly your route, the bluff already fails here.

Question 2: does your hand really have no showdown value?

Bluff with your worst hands, not with your middling ones. A missed flush draw with a low card practically never wins by checking: perfect bluffing material. A small pair does win occasionally by checking, and that small chance is free. Check hands with residual value, bluff or give up hands without it: that simple split prevents the expensive classic where you bluff away a pair that had won on its own.

Question 3: do you hold the right blockers?

Your own cards tell you which strong hands your opponent cannot have. If a third heart lands on the river and you hold the ace of hearts, the best flush is impossible for him; your card blocks that hand. Such blockers make your bluff demonstrably safer, because you cross off exactly the hands you will never get to fold. How that crossing off works is in the blockers explained.

Question 4: can this opponent fold?

The finest bluff in the world loses to a player who pays anyway. At low stakes calling stations are the rule rather than the exception: players who call every river bet with any pair. Against them you simply do not bluff, however perfectly the rest of the checklist scores. Save your bluffs for opponents who can demonstrably lay hands down, and pay calling stations back by value betting thinner against them.

For that judgement, look at what you saw earlier. If this player has already laid down top pair after a big bet, that is worth gold as information. If instead you saw him go to showdown twice with third pair, you also know enough. Without information the safe assumption holds at low stakes: the average opponent folds too little, so bluff too rarely rather than too often.

Question 5: does the size match the sum?

If you bet two thirds of the pot, the bluff has to succeed in roughly 40 percent of cases to break even; with a half pot bet a third is enough. So choose the smallest size that still does the job: big enough to chase away the hands you want to chase away, no bigger. And note the hand afterwards, successful or not. River decisions in particular teach you the most when reviewing your hands, because there the whole story becomes visible at once. The sum also changes how you look at losses: a bluff that succeeds four times in ten at a two thirds pot bet already breaks even, so a single failed bluff proves no mistake. Judge the decision, not the outcome: if you ran through the five questions properly, the bluff was good, whatever the opponent turned over.