Those Roulette Edges

3 September 2023

By John Grochowski

QUESTION: When you calculate the house edge in roulette, you always use single-number bets or the even-money payoff bets where you get 18 numbers (red or black, odd or even, 1-18 or 19-36).
What about something in between like the corners or columns? How do they wind up in the same place as singles or red/black?

ANSWER: Roulette lends itself to easy arithmetic and a well-defined house edge that's kept the game in casinos since the late 1700s.

Payoffs are based on true odds for a 1-36 number set. If there were only 36 numbers on the wheel, roulette would be an even proposition with no house edge. But there are 37 numbers with a single zero, 38 with 0 and 00 or 39 in the triple-zero games that now dot the Las Vegas Strip.

Imagine you wagered $1 per spin and every number turned up once. You'd risk $37 on a single-zero wheel, $38 on a double-zero wheel and $39 on a triple-zero abomination.

Four-number corner bets pay 8-1. If each of your winners came up once, you'd get $32 in winnings plus keep $4 on the winning wagers. That would leave $36 on your side of the table.

Subtract that from the wager totals and you've lost $1 on a single-zero wheel, $2 with double zero and $3 with triple zero.

Divide the $1 in casino profit by $37 risked in single-zero roulette, and you get 0.027. Multiply by 100 to convert to percent, and the house has a 2.7 percent edge.

With a $2 profit vs. $38 in wagers, the house edge at double-zero is 0.0526, or 5.26 percent. And the $3 in profit divided by $39 in wagers at triple zero means the house edge is 0.0769, or 7.69 percent.

If you've been betting $1 on 12-number columns instead, payoffs are 2-1. Each of your 12 winners brings $2 in profit plus you keep the $1 wagers. That leaves you with a total of $36 -- the same total you have after four winners on corners.

We know where it goes from there. House profits are $1 on a single-zero wheel, $2 at double-zero and $3 at triple-zero, leading to respective house edges of 2.7, 5.26 and 7.69 percent.

Those are the same house edges at each zero-level as you'll find on nearly every wager. In casinos that offer special rules such as Atlantic City's half-back or the French en prison, the edge on 18-number bets can be cut in half. And the five-number "basket" of 0, 00, 1, 2 and 3, offered only on double-zero wheels, increases the house take to 7.89 percent.

Otherwise, edges are the same, though results are more volatile when you have fewer numbers in action.


QUESTION: I have a back-to-back jackpots story for you, or maybe it's side by side. Usually, my wife plays slots while I play video poker. This time, she decided to play video poker next to me.

We both were playing quarters on single-hand games. She was on Double Double Bonus and I was on Super Double Bonus. I had a Jack, Queen and Ace of clubs on my screen and was about to hit the button, when I got an elbow. "Look! Look! Look!"

Jen had four Aces and a 3 of hearts for $500. She'd held three Aces and drew the other two, and she was thrilled.

Then I hit draw, and I got my royal!

Jen was mock exasperated. "Oh, sure. I get my best hand ever and you had to one-up me." She high-fived me anyway.

ANSWER: Good story! Thanks for sharing.