American and European Roulette - Different Roulette Rules

A look at the similarities and differences between the roulette wheel, the house edge and the rules of American roulette and European roulette games.

The basic game of roulette is the same whether you play the American version of the game or you play the European version of the game. There are however a few minor differences and it is important to understand them as they may affect which version of the game you choose to play.

The Difference in the Wheel and Odds

The main difference between American roulette and European roulette is in the wheel. European roulette wheels have the numbers 1 through 36 plus a single zero slot. American roulette wheels, on the other hand, have the numbers 1 through 36, a single zero and a double zero slot. This means that in the European version of the game, there are 37 slots in total, making the odds of the ball landing on a specific number, 1 in 37. In American roulette, there are 38 slots, however, making the odds of the ball landing on a specific number, 1 in 38. The double zero was added to the American roulette wheel in order to increase the house edge, and thus decrease the player's odds.

House Advantage in American roulette vs. European Roulette

Due to the added double zero slot on the American roulette wheel, the house advantage in this version is 5.26%.

In European roulette, where there is only the single zero, as opposed to the double zero as well in American roulette, the house advantage goes down from 5.26% to 2.63%. This minor difference (of one extra slot) between the wheels makes a very large difference between the house advantages – playing European roulette will halve it.

Optional Rule in European Roulette

European roulette offers an optional rule known as the "en prison" rule. This rule makes the game even more attractive. If you bet on an even money bet and the ball lands on the single zero, the player can make use of the "en prison" option. This literally means that your bet will be in prison – or held, until the next spin. In other words, instead of losing your bet on that round, you can keep your bet over until the next spin. If the next spin lands on your bet, you will win your bet back (though you will not come out ahead). On the other hand, if you lose the next spin as well, you will then lose you bet. This can reduce the house edge down further to 1.35%.

This option is not available in American roulette.

Similarities between American and European Roulette

Besides for the difference in the wheel between American and European roulette, everything else is the same. They both use a white ball that spins on red and black numbers (with the single zero and double zero in green).

You can place the same bets in the two versions of the game.

The rules of play are the same between the two versions (except for the optional "en prison" rule that we mentioned above that is available in European roulette).