Lowball

Some forms of poker, often called lowball, sometimes called “low poker,” reward poor poker hands (in the traditional sense). There are three common variations on this idea, differing in whether aces are treated as high cards or low cards, and whether or not straights and flushes are used. The methods are:

Ace-to-five low: The lowest possible hand is -4-3-2-A, called a wheel. Aces are low and straights and flushes are ignored. This is the most common method.
Ace-to-six low: Also called

-4-3-2-A. Aces are low and straights and flushes count as high hands.

Deuce-to-seven low: Also called
-5 low, since the lowest possible hand is -5-4-3-2. Almost the direct inverse of traditional “high hand” poker. Aces are high and straights and flushes count as high hands. Since aces are high, A-5-4-3-2 is not a straight, but just ace-high no pair.

Deuce-to-six low: The other, mostly unused, possibility would be

-5 low. Aces are high, straights and flushes are ignored.

Some games are played high-low split, where the player with the best traditional poker hand (called the “high hand”) splits the pot with the best low hand. The low hand is decided by one of the methods above. According to Official Rules of Card Games by Albert Morehead [1], the low hand in high-low is generally the deuce-to-seven low, although many on-line casinos use ace-to-five low, with a qualifier, e.g., no card higher than an 8. Low hands tie more frequently than high hands, especially in community card games, so it is not uncommon for such a hand to win a small fraction of a poker pot. For example, if one player has the high hand on showdown, and two other players tie for the best low hand, the high hand wins half of the pot and each low hand wins only a quarter of the pot. Playing ace-to-five high-low greatly increases the chances of the “scoop”–winning both hands–because a low flush or straight may count for both high and low.