Heads-up
One against one. The blinds swap roles — the button is the small blind and acts first before the flop, last after — and ranges widen enormously.
Heads-up is the same game with two players and one structural difference that catches everyone out: the button posts the small blind. That means the button acts first before the flop and last on every street after it — the opposite of the order at a full table, and the reason heads-up hands feel wrong the first few times you play them.
Everything else follows from the arithmetic of two players. There are no seats to fold through, so you are in a blind every hand and paying for the privilege of waiting. A range that plays fifteen percent of hands at a full table is unplayable here: the button opens something like eighty percent, and the big blind defends with most of what is left. Hands that are trash six-handed — king-four offsuit, seven-five suited — are ordinary holdings heads-up, because the only question is whether they beat a random hand rather than whether they beat five of them.
It also strips the game down to the parts that are hardest. There is no third player to fold and let you off the hook, so every pot is a two-way argument decided by who reads the other better. Aggression rewards more and punishes more, and stack depth changes the whole game: under about fifteen big blinds, heads-up collapses into push or fold.
The beginner mistake is bringing full-ring ranges to a heads-up table. Folding the small blind seventy percent of the time hands over a blind and a half every orbit to someone who is not required to show you a hand, and it takes very few orbits for that alone to be the whole loss.
FAQ
Who is the small blind in heads-up poker?
The button. In a two-player game the dealer posts the small blind and the other player posts the big blind, so the button acts first before the flop and last on every street after it — the reverse of the order at a full table.
How wide should you play heads-up?
Far wider than at a full table. The button opens something in the region of eighty percent of hands and the big blind defends with most of what remains. You are in a blind every hand, so folding your way to a profit is not available.
Why is heads-up poker harder?
Because there is nobody else to fold. Every pot is a two-way contest decided by reading the other player, marginal hands are played rather than passed, and mistakes repeat every single hand instead of once an orbit.