What Is the House Advantage in Roulette?

In casino games, the “house edge” refers to the percentage of each bet that the casino expects to keep over the long run-thousands or even millions of bets. The higher the house edge, the worse the odds are for the player.

For example, a game with a 5 percent house edge will cost a player $5 for every $100 bet.

Roulette is a good example of a high-house-edge game. The most common type of roulette played in North American casinos has 38 possible outcomes-1 through 36, 0, and 00. The probability of any one of those numbers coming up on a spin is 1 in 38, or 2.63 percent. But if you bet on just one number, you’re only paid 35 to 1 if it hits.

So your expected loss on each bet is 2.63 percent x 35, or 91.825 cents. (The actual house edge is higher because of the 0 and 00; more on that later.).

The house edge in roulette comes from the fact that there are more possible outcomes than there are corresponding payouts. For example, if you bet on red or black, you have 18 possible outcomes (any of the 18 red numbers or any of the 18 black numbers) and only 2 corresponding payouts (1 to 1 for a win, and nothing for a loss).

So your expected loss is 18/38 x 1, or 47.368 cents per $1 bet.

The 0 and 00 add another layer of complexity to roulette. If you bet on red or black and one of these numbers comes up, you lose your entire bet. That increases the house edge to 5.26 percent on these bets (18/38 x 2 = 5.

26). If you bet on just one number, your expected loss is increased even more because now you’re only paid 35 to 1 instead of 36 to 1 if your number hits (1/38 x 35 = 0.947).

So what’s the bottom line? The house edge in roulette varies depending on what type of bet you make, but it’s always going to be positive-meaning the casino will always have an advantage over time. If you’re looking for a game with the best odds for winning, stick to something else!.