Casino
Roulette Odds and Probability: How the House Edge Works
Roulette is one of the purest games of chance in the casino. Once the wheel is spinning, no decision changes where the ball lands. What you can control is where you place your chips, and that starts with understanding the numbers behind every bet.
Roulette odds are fixed by the wheel design. European roulette, with a single zero, carries a 2.70% house edge. American roulette, with a double zero, 5.26%. Payouts sit just below the true probability of each bet, and that gap is the house edge.
Complete Roulette Odds and Payouts Table
The table below covers every standard bet type, with roulette payouts, probability, and house edge figures for both European and American wheels. The Five Numbers bet applies only to American roulette and carries a higher house edge of 7.89%.
Bet type | Payout | European Roulette Odds | European Roulette House Edge | American Roulette Odds | American Roulette House Edge |
Colour | 1:1 | 48.65% | 2.70% | 47.37% | 5.26% |
Odd / Even | 1:1 | 48.65% | 2.70% | 47.37% | 5.26% |
Lows / Highs (1-18 / 19-36) | 1:1 | 48.65% | 2.70% | 47.37% | 5.26% |
Dozens | 2:1 | 32.43% | 2.70% | 31.58% | 5.26% |
Columns | 2:1 | 32.43% | 2.70% | 31.58% | 5.26% |
6 Numbers (6 line) | 5:1 | 16.22% | 2.70% | 15.79% | 5.26% |
5 Numbers (top line) | 6:1 | – | – | 13.16% | 7.89% |
4 Numbers (square) | 8:1 | 10.81% | 2.70% | 10.53% | 5.26% |
3 Numbers (street) | 11:1 | 8.11% | 2.70% | 7.89% | 5.26% |
2 Numbers (split) | 17:1 | 5.41% | 2.70% | 5.26% | 5.26% |
1 Number (straight) | 35:1 | 2.70% | 2.70% | 2.63% | 5.26% |
What the House Edge Means in Practice
The house edge is the built-in difference between the true probability of a winning bet and the payout attached to it. A straight-up number on a European wheel hits 1 in 37 times, but it pays 35:1. That structure applies across the board, from even-money wagers to inside bets.
The gap exists on every spin and on every standard bet type. It does not disappear because a wheel has just paid out, because a player is following a favourite pattern, or because a sequence of results looks unusual. Roulette betting systems and strategies can change how a session is paced, but they don’t change the underlying roulette probability or roulette house edge.
European Roulette vs American Roulette
European roulette has 37 pockets: numbers 1 to 36 plus a single zero. American roulette has 38 pockets: numbers 1 to 36 plus zero and double zero. That single extra pocket is enough to nearly double the house edge from 2.70% to 5.26%.
The payouts on the board look the same on both wheel types, but the extra zero reduces the chance of winning on every standard bet. For anyone who wants the better mathematical position, European roulette is the cleaner choice.
En Prison and La Partage on Even-Money Bets
Some European roulette tables offer en prison or la partage rules on even-money bets. These rules apply only to wagers such as red/black, odd/even, and high/low – you can find definitions for all of these in the roulette terms glossary.
When the ball lands on zero, en prison keeps your stake in play for one more spin. La partage returns half your stake immediately. Both rules cut the house edge on those even-money bets to roughly 1.35%, well below the standard European figure.
Why Gambler’s Fallacy Does Not Work
Each spin of the wheel is independent. Past results don’t influence the next result, and the wheel doesn’t record what happened before. The chance of red after ten consecutive blacks is exactly the same as the chance of red on any other spin.
That’s why gambler’s fallacy is a persistent trap in roulette probability discussions. A long run of one colour doesn’t make the opposite more likely on the next spin, and it doesn’t bring a specific number closer to hitting.
Consecutive Outcomes and Streaks
Repeated outcomes can and do happen, and the probability compounds over a sequence. On a European wheel, the chance of the same number landing twice in a row is 1 in 1,369 – that figure comes from multiplying 1-in-37 by 1-in-37. Three times in a row extends to 1 in 50,653, and so on.
What doesn’t change is how roulette payouts are settled. Bets are resolved on individual spins, so a straight-up win still pays at 35:1 regardless of how many times that number has appeared already. Streaks may be interesting to watch, but they carry no weight on the next spin.
Key Takeaways
- European roulette carries a 2.70% house edge; American roulette carries a 5.26% house edge.
- European roulette uses 37 pockets; American roulette uses 38 because of the extra double zero.
- En prison and la partage can reduce the house edge on even-money bets to around 1.35% on eligible European tables.
- Each spin is independent; gambler’s fallacy doesn’t change roulette odds or probability.
- No betting pattern, system, or bet type changes the underlying house edge.
