The standards for American and European roulette are not the same. While you may find European roulette in the United States, especially in a European-themed casino, there are differences in the customary styles for each area. Roulette did originate France in the 18th century, but when the wheels entered the United States in the 19th century, some changes were made. Some of the earliest American-style roulette wheels were seen in the 1886 edition of the Hoyle's gambling book, with an extra slot not seen on the traditional European wheels.
The American live roulette wheel has a slot that European roulette wheels don't, the "00." European wheels, known as "single-zero" wheels, have 37 slots. Only zero and the numbers one to 36 are used on European roulette wheels.
American roulette wheels, on the other hand, have 38 slots. American wheels have the same numbers for the slots as the European wheels but also include a slot for a double zero.
The player odds for a single number coming in on an American wheel are worse than the player odds on a European wheel. Odds on an American wheel are 37 to 1, versus 36 to 1 for a European wheel.
Since roulette pays out an average 35 to 1 each bet, the house advantage for an American wheel stands at an estimated 5.26 percent. For every $100 bet, the player can expect to lose an average of $5.26.
The house advantage on a European roulette wheel stands at around 2.70 percent. For the player betting $100 on a European wheel, the loss average drops to about $2.70.
Basic game play is still the same in both the European and American versions of roulette. The betting system, however, is different in some casinos.
In American roulette, the player buys chips before the game. The chips already have assigned value. For example, all green chips may equal $25. The player bets on roulette using the chips and cashes the chips in for money when he's finished.
In European roulette, chips may have varying values, depending on the casino. Both the player and the croupier must keep track if chips with differing values are used with the same colors. This betting system relies on honestly and the ability of those involved to keep track of the bets.
Traditional European roulette tables are sometimes larger than American roulette tables. While this should not affect actual game play, some players prefer a smaller table for betting purposes in a live casino.
American roulette does not have the en prison rule used in European roulette. The rule allows players who land on zero to surround half of their outside bets or hold to the next round. When the rule is in effect, it drops the house's advantage to around 1.3 percent.
A player might be able to find both American and European roulette wheels in the same casino, no matter where the location. Some European-themed casinos in the United States, such as the Monte Carlo in Las Vegas, offer both formats.