Roulette looks identical from table to table: a spinning wheel, a ball, a felt layout of red and black numbers. But the version you sit down at changes the house edge by a factor of two, and a third variant with a couple of extra rules cuts it in half again. The differences are entirely down to how many green pockets the wheel has and what happens when the ball lands in one.
European roulette
The European wheel has 37 pockets: the numbers 1 to 36 plus a single green zero. A bet on one number pays 35 to 1.
If the game were fair, a single number would pay 36 to 1, because there are 36 ways to lose against one way to win. The difference between the fair payout (36) and the actual payout (35) is where the house edge lives. Expressed as a percentage it is 1/37, or 2.70%. On average, for every £100 bet on a European wheel, the casino expects to keep £2.70.
American roulette
The American wheel adds a second green pocket, the double zero, for 38 in total. Payouts are unchanged — a single number still pays 35 to 1 — but there are now 37 losing pockets. The house edge becomes 2/38, or 5.26%. Every bet on the table is nearly twice as expensive over time.
American wheels are the standard in Las Vegas and much of the United States. They are less common in the UK, but they appear in some online lobbies, often with graphics that make the extra pocket easy to miss.
French roulette
French roulette uses a European single-zero wheel with one or both of two additional rules that apply to even-money bets (red/black, odd/even, high/low):
- La Partage: if the ball lands on zero, half of your even-money stake is returned.
- En Prison: if the ball lands on zero, your even-money stake stays on the table “in prison” for the next spin. Win that spin and the stake is returned; lose and it is taken.
Either rule cuts the house edge on even-money bets to 1.35%. The edge on all other bets stays at 2.70%. Not every online casino offers French rules, so it is worth reading the game information.
Comparison at a glance
| Variant | Pockets | Zeros | House edge (most bets) | House edge (even-money with La Partage) |
| European | 37 | 1 | 2.70% | n/a |
| French | 37 | 1 | 2.70% | 1.35% |
| American | 38 | 2 | 5.26% | n/a |
Why the edge is the same on every bet
On a European wheel, whether you bet a single number, a split, a street, a corner, a dozen or red/black, the maths works out to the same 2.70%. The payouts are structured so that no bet type is better or worse than another over time.
| Bet | Numbers covered | Payout | Probability (European) | House edge |
| Straight up | 1 | 35:1 | 2.70% | 2.70% |
| Split | 2 | 17:1 | 5.41% | 2.70% |
| Street | 3 | 11:1 | 8.11% | 2.70% |
| Corner | 4 | 8:1 | 10.81% | 2.70% |
| Dozen/column | 12 | 2:1 | 32.43% | 2.70% |
| Red/black, odd/even | 18 | 1:1 | 48.65% | 2.70% |
The one exception is on American wheels: the five-number “basket” bet (0, 00, 1, 2, 3) pays 6 to 1 and carries a house edge of 7.89% — the worst bet on the table.
Betting systems
The Martingale (double your stake after every loss), the Fibonacci, the D’Alembert and countless others are widely promoted. None of them changes the house edge, because each spin is independent and the edge is applied to every stake placed. What systems do change is the pattern of results: Martingale produces many small wins and occasional catastrophic losses when a long losing run meets the table maximum or the player’s bankroll. A wheel that has landed on red ten times in a row has exactly the same probability of red on the eleventh.
Practical points for online play
- Look for a single zero on the wheel graphic and in the game rules.
- Check whether La Partage applies; it is sometimes offered under a different name.
- Live dealer roulette usually has higher minimum stakes than RNG versions.
- Some online variants add side bets or multipliers (“lightning” style games). These typically reduce the base payouts to fund the extras, and the overall RTP is usually lower than standard European roulette.
Related reading on site: Casino Guide; “The Most Popular Casino Games in the UK”.
Casino games are designed with a house edge. Decide what you’re willing to spend before you sit down.
