A European roulette wheel has 37 pockets: the numbers 1 to 36 and a single zero. An American wheel has 38, because it adds a double zero. The payouts are the same on both, so that one extra pocket nearly doubles the house edge, from 2.70% to 5.26%. Below, every standard bet is worked out on both wheels, along with the one bet that is worse than all the others.
Why every bet has the same edge
Roulette payouts are set as if the wheel had only 36 numbers. A straight-up bet on one number pays 35 to 1, so a win returns 36 units for each unit staked: your stake plus 35. The same holds for every standard bet: the numbers covered × (payout + 1) = 36.
Worked example: Bet 1 unit on a single number for 37 spins of a European wheel. On average you win once and get 36 back, having staked 37 in total. You lose 1 unit in 37, which is 2.70%. On an American wheel you stake 38 to get the same 36 back, losing 2 in 38, or 5.26%.
In general, the house edge is 1 − 36 ÷ the number of pockets: 1 ÷ 37 on a single-zero wheel and 2 ÷ 38 on a double-zero wheel. The zeros are the casino's share.
Every bet on both wheels
| Bet | Numbers | Pays | Chance, European | Chance, American | Edge, European | Edge, American |
|---|---|---|---|---|---|---|
| Straight up | 1 | 35 to 1 | 2.70% | 2.63% | 2.70% | 5.26% |
| Split | 2 | 17 to 1 | 5.41% | 5.26% | 2.70% | 5.26% |
| Street | 3 | 11 to 1 | 8.11% | 7.89% | 2.70% | 5.26% |
| Corner | 4 | 8 to 1 | 10.81% | 10.53% | 2.70% | 5.26% |
| Six line | 6 | 5 to 1 | 16.22% | 15.79% | 2.70% | 5.26% |
| Dozen or column | 12 | 2 to 1 | 32.43% | 31.58% | 2.70% | 5.26% |
| Red/black, odd/even, low/high | 18 | 1 to 1 | 48.65% | 47.37% | 2.70% | 5.26% |
| Five-number (0, 00, 1, 2, 3) | 5 | 6 to 1 | — | 13.16% | — | 7.89% |
The five-number bet
The five-number bet exists only on the double-zero wheel. It covers 0, 00, 1, 2 and 3 and pays 6 to 1, so a win returns 7 units: 5 numbers × 7 = 35, one short of the 36 every other bet gets. That missing unit raises the house edge to 3 ÷ 38 = 7.89%, the worst bet on the table.
La Partage and En Prison
Some single-zero tables, especially French ones, soften the zero for even-money bets. Under La Partage, when the ball lands on zero you get half of an even-money stake back. Under En Prison, the stake is held for the next spin instead. Either rule cuts the edge on those bets to about 1.35%: with La Partage, half a unit lost once in 37 spins is 0.5 ÷ 37. Every other bet keeps the usual 2.70%.
What the edge costs in a session
Worked example: 100 spins at 10 a spin means 1,000 staked. The average loss is 27.03 on a European wheel, 52.63 on an American wheel and 13.51 on even-money bets with La Partage.
The averages say nothing about a single session, but they decide where a long run of sessions ends up.
Same edge, different ride
Red and a single number cost the same on average, but they feel very different. On a European wheel, red wins about once every two spins. A single number wins once in 37 on average, and in 100 spins there is a 6.5% chance it never comes up at all. Choosing riskier bets changes how much your balance swings, not how much the game costs.
Check any bet on any wheel with the roulette calculator.
- European wheel: 37 pockets and a 2.70% house edge on every standard bet.
- American wheel: 38 pockets and a 5.26% edge, plus a five-number bet at 7.89%.
- La Partage or En Prison cuts the edge on even-money bets to about 1.35%.
- Bet choice changes how much your balance swings, not the average cost.
Sources
- Roulette — Wikipedia: wheels, payouts and house edge
- Roulette basics — Wizard of Odds: bets, payouts and house edge on both wheels
18+ only. No betting system changes the house edge. See our Responsible Gambling page.
RTP Data explains the mathematics of casino games, with every figure sourced or worked out in the text.