In the traditional game of roulette, whether it is the single zero version or the double zero version, when the ball lands on the zero or the double zero, the player loses, unless he has bet on the zero or the double zero. Roulette is also popular game like bingo, blackjack etc. are. This gives the house the advantage in both versions.  In the American version, with the double zeros, the house advantage is 5.26%.  The European version, with its single zero, has a house advantage of 2.7%.  Regardless of which version the player plays, there is no way to lower the house advantage, which is one of the reasons why betting systems are useless in roulette.

Some casinos offer the game with the “En Prison” rule. This rule affects outside bets and what happens to them when the ball lands on the zero or double zero. The player doesn’t automatically lose his bet as he does in the traditional game. The bet is held, or is en prison, until the outcome of the next spin. If the bet is a winner on the next spin, the bet is returned to the player. He doesn’t receive any winnings, just the bet. The existence of the en prison rule lowers the house advantage on even money bets to 2.63% in the American version and 1.35% in the European version. This changes the casino game for the player who has a much better chance in the game with the en prison rule. Roulette players should look for these advantages at the casinos.