Roulette House Edges

13 August 2023

By John Grochowski

QUESTION: Some of the things you've written about roulette seem curious to me. You wrote that on a double-zero wheel, a bet on a single number has a 5.26 percent house edge, but if you bet on red or black, the house edge is also 5.26 percent.

I'm not seeing how they can be the same. You have a lot more chances to win on red or black while you're going to lose almost all the time on a single number.

I looked online, and others list the same edges you do. Are the games fixed so the house keeps that 5.26 percent no matter what?

ANSWER: Roulette is "fixed" only in the sense that the probabilities are set so that random results will lead to the house keeping 5.26 percent of money wagered on nearly all bets on a double-zero game.

Bets that are vastly different experiences can have the same house edge. Bets on red or black win a lot more often than bets on a single number, but the payoff for a red/black winner is even money while a winning single number pays 35-1.

A bettor who wants to take a shot at a big win in one shot might like the single number. One who wants to make play last a longer time and take a chance at grinding out a small profit might stick with red/black.

Imagine there are 38-wheel spins and each number, including 0 and 00, comes up once. If you bet $1 on red each time for a total risk of $38, you win 18 times. On each winner, you will keep your $1 bet and receive $1 in winnings. That leaves you with $36 while $2 is in the house coffers. That $2 represents 5.26 percent of your wagers, and that's the house edge.

Let's say I bet $1 on No. 17 on each of those spins, I'll win only once, but my winnings will be $35. I also keep my $1 bet on the winner, leaving me with $36, just like you. The house has kept $2 from my wagers and has its 5.26 percent.

We've taken vastly different routes, but we've wound up in the same place.

Numbers won't come up in perfect proportions every 38 spins. If you have a run with red coming up more often than average, you can grind out a profit. If my single number hits more than once per 38 spins, I can make money.

But the house is in it for the long haul. Streaks and counter-streaks will fade into statistical insignificance, and the house can count on its edge.


QUESTION: I tried an electronic table where you could switch between craps, roulette, blackjack and sic bo. I never played sic bo before, so I tried a little and was mostly confused. What are the best bets?

ANSWER: Sic bo is not common in the U.S., though some large casinos have tables. It involves three dice in a birdcage on a swivel. The cage is turned upside down to roll the dice. On electronic tables, the dice can be rolled by a random number generator.

There are many possible combination bets, too many to detail them all in this small space. You'll find the lowest house edges on "big" and "small."

You win on big if the three dice total 11-17, but lose on three of a kind. Small wins on totals of 4-10, except three of a kind. The house edge on either is 2.78 percent, a bargain in a game where most house edges are in double figures.