House Advantage

A house advantage in roulette or in any casino game (also known as house edge, house average or expected value) is the difference between the player’s true odds and the payouts for the bets he/she wins. For instance, if a player has placed a bet on one number in American roulette, the probability of him winning the bet is 1/38, while the probability of him losing the bet is 37/38. In other words:

Compared to European roulette, if he places a bet on one number, there is a 1⁄37 chance that he wins the bet and there is 36 out of 37 probability of him losing the bet.

The house advantage depends on the number of zeros on the roulette wheel and this depends on the roulette variant you want to play. A bet is often lost if one or two zeros come up.

Additionally, there is also house edge on inside bets. The reason behind this is that if, for instance, you place a straight bet on single number, there is a 1 out of 38 probability of winning that bet and the payout is set at 35 to 1. To understand how this works, imagine that you have placed €1 wagers on all inside numbers. Having spent €38, winning will get you back 36 times your original bet. The exception here is the five numbers bet where, in American roulette, the house edge is 7.89%.

The special rules such as En Prison, Surrender etc. usually reduce the house advantage with the equal chance bets till 1,35% in European roulette and till 2,63% in the American variant of the game.