Ace-to-five low

Lowball or low poker is a variant of poker in which the normal ranking of hands is inverted. Several variations of lowball poker exist, differing in whether aces are treated as high cards or low cards, and whether straights and flushes are used.

Lowball inverts the normal ranking of poker hands. There are three methods of ranking low hands, called ace-to-five low, deuce-to-seven low, and ace-to-six low. The 'ace-to-five' method is most common. A sub-variant within this category is 'high-low poker', in which the highest and lowest hands split the pot, with the highest hand taking any odd chips if the pot does not divide equally. Sometimes straights and/or flushes count in determining which hand is highest but not in determining which hand is lowest, being reckoned as a no-pair hand in the latter instance, so that a player with such a holding can win both ways and thus take the entire pot.

The most popular forms of lowball are ace-to-five lowball (also known as California lowball), and deuce-to-seven lowball (also known as Kansas City lowball). Ace-to-five lowball gets its name because the best hand at that form is 5-4-3-2-A. In ace-to-five lowball straights and flushes do not prevent a hand from being low. You win by simply having the five lowest cards. Deuce-to seven lowball gets its name because the best hand at that form is 7-5-4-3-2 (not of the same suit).

Ace-to-five low is the most common method for evaluating low hands in poker, nearly universal in U.S. casinos, especially in high-low split games.

As in all low hand games, pairs count against the player. That is, any hand with no pair defeats any hand with a pair; one pair hands defeat two pair or three of a kind, etc. No-pair hands are compared starting with the highest-ranking card, just as in high poker, except that the high hand loses. In ace-to-five low, straights and flushes are ignored, and aces play as the lowest card.

For example, the hand 8-5-4-3-2 defeats 9-7-6-4-3, because eight-high is lower than nine-high. The hand 7-6-5-4-3 defeats both, because seven-high is lower still, even though it would be a straight if played for high. Aces are low, so 8-5-4-3-A defeats 8-5-4-3-2. Also, A-A-9-5-3 (a pair of aces) defeats 2-2-5-4-3 (a pair of deuces), but both of those would lose to any no-pair hand such as K-J-8-6-4. In the rare event that hands with pairs tie, kickers are used just as in high poker (but reversed): 3-3-6-4-2 defeats 3-3-6-5-A.

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