Spanish 21

Spanish 21 is a blackjack variant owned by Masque Publishing Inc., a gaming publishing company based in Colorado. Unlicensed, but equivalent, versions may be called Spanish blackjack. In Australia and Malaysia, an unlicensed version of the game, with no dealer hole card and significant rule differences, is played in casinos under the name "Pontoon". It was first introduced into Nevada casinos in about 1995.

Spanish 21 is played on a blackjack table with a custom layout and uses the following rules:

The removal of the four tens in each deck gives roughly a 2% advantage to the dealer. The liberal rules of Spanish 21, though, do compensate for this. With optimal play, the house edge of a Spanish 21 table is lower than that of a blackjack table with the same rules on hitting or standing on soft 17.

The game also offers an optional "Match the Dealer" side bet, which compares a player's cards with the dealer's upcard. Matching the rank of the dealer's card pays 4:1 on a six-deck game, and 3:1 on an eight-deck game, while a "perfect match" of rank and suit pays 9:1 on six decks and 12:1 on eight decks. A player may win on both cards; (e.g. if a player has 8s 8c and the dealer has 8c as an upcard, the player will receive 3:1 on the rank match and 12:1 on the perfect match, paying out a total of 15:1.) While this side bet has a house edge of approximately 3%, significantly higher than the edge of the main game, it is one of the lowest house edges of any blackjack side bet.

Masque Publishing, the owners of this game, maintains a list of venues that offer S17 or redoubling rules [1].

The following tables list the Spanish 21 house edges for all rule sets found in North America. (The figures were obtained from 10-billion hand simulations and have a standard error of 0.001%. The super bonus is averaged out to a 100:1 payout.) These charts assume that the player is using basic strategy. "H17" means that the dealer hits soft seventeen, "S17" means that the dealer stands on soft seventeen.

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