Roulette in 4 lines
- You bet on where the ball will land. Bets on fewer numbers pay more.
- A European wheel has 37 pockets: 1 to 36 plus a single green zero.
- Every bet on a European wheel has the same house edge, 2.70%, because the zero isn't paid for.
- American wheels add a double zero, which nearly doubles the edge to 5.26%. Pick the single-zero game.
How a round of roulette works
You place chips on the betting layout, the table printed with the numbers 0 to 36. Each spot on the layout is a different bet. When the dealer calls "no more bets", the wheel spins one way and the ball spins the other.
The ball drops into one numbered pocket. Bets that cover that number are paid, everything else is taken, and the next round starts. In an online game a random number generator picks the pocket; in live dealer roulette a real wheel is filmed in a studio.
Payouts are quoted "to 1". A bet that pays 35 to 1 returns your stake plus 35 times it, so £1 on a single number that wins gives you £36 back.
European, American and French wheels
European roulette has 37 pockets: the numbers 1 to 36, half red and half black, plus a green 0. It's the standard game at UK casinos online.
American roulette adds a second green pocket, 00, making 38. The payouts stay the same, so the extra pocket goes straight to the house.
French roulette uses the European wheel and often adds the La Partage rule, which gives back half of an even-money bet when the ball lands on 0. More on that below, because it's the one rule that genuinely lowers the cost of playing.
Every bet, what it pays and your chance of winning
Inside bets go on the numbers themselves. Outside bets go on the groups printed around the edge of the layout. Figures are for a European single-zero wheel.
Tap or click any bet on the layout to see what it pays, your chance of winning it and the house edge. On a keyboard, tab to the layout, move across the numbers with the arrow keys (off the edge of the numbers reaches the outside bets and chips) and press Enter. It shows the maths only: nothing is staked.
Red Red or black bet, 18 numbers
- Pays
- 1 to 1
- Chance of winning
- 48.65%18 in 37
- House edge
- 2.70%
£1 on it for 37 spins, on average: it wins 18 times (+£18) and loses 19 times (−£19). That leaves £1 lost for every £37 staked: 1 ÷ 37 = 2.70%.
| Bet | Covers | Pays | Chance of winning | House edge |
|---|---|---|---|---|
| Straight up | A single number, including 0 | 35 to 1 | 2.70% (1 in 37) | 2.70% |
| Split | Two numbers next to each other on the layout | 17 to 1 | 5.41% (2 in 37) | 2.70% |
| Street | A row of three numbers | 11 to 1 | 8.11% (3 in 37) | 2.70% |
| Trio | 0, 1 and 2, or 0, 2 and 3 | 11 to 1 | 8.11% (3 in 37) | 2.70% |
| Corner | A block of four numbers | 8 to 1 | 10.81% (4 in 37) | 2.70% |
| First four | 0, 1, 2 and 3 | 8 to 1 | 10.81% (4 in 37) | 2.70% |
| Six line | Two rows, six numbers | 5 to 1 | 16.22% (6 in 37) | 2.70% |
| Dozen | 1 to 12, 13 to 24 or 25 to 36 | 2 to 1 | 32.43% (12 in 37) | 2.70% |
| Column | One of the three long columns of 12 | 2 to 1 | 32.43% (12 in 37) | 2.70% |
| Red or black | 18 red or 18 black numbers | 1 to 1 | 48.65% (18 in 37) | 2.70% |
| Odd or even | 18 odd or 18 even numbers | 1 to 1 | 48.65% (18 in 37) | 2.70% |
| Low or high | 1 to 18 or 19 to 36 | 1 to 1 | 48.65% (18 in 37) | 2.70% |
The last column is the same all the way down. That surprises people, but it follows from the payouts: each one is worked out as if the wheel had 36 pockets, and the 0 is the 37th.
Where the 2.70% house edge comes from
Take £1 on a single number. You win £35 once in 37 spins on average, and lose £1 the other 36 times. Over 37 spins that's £35 won and £36 lost, a net loss of £1 for every £37 staked: 1 ÷ 37 = 2.70%.
Red or black works the same way. There are 18 red numbers, 18 black and the 0. Bet £1 on red 37 times and on average you win 18 times (+£18) and lose 19 times (−£19). Same £1 lost per £37 staked.
On an American wheel there are 38 pockets and the same payouts, so the loss is £2 for every £38 staked, 5.26%. The one bet that's worse still is the American five-number bet on 0, 00, 1, 2 and 3. It pays 6 to 1 and carries a 7.89% edge.
What the house edge costs you in practice
The edge is an average over a very large number of spins. Say you play 100 spins at £10 each on a European wheel. That's £1,000 staked, and the expected loss is 2.70% of it: £27.
Your real result will almost never be exactly £27 down. In a short session you might finish well ahead or well behind, and that swing is what makes the game exciting. But the more you play, the closer your loss as a share of everything you've staked tends to sit to that 2.70%. Treat the expected loss as the price of the entertainment and decide in advance how much you're happy to pay.
La Partage and En Prison
Some French and European tables use one of two rules on even-money bets (red or black, odd or even, low or high) when the ball lands on 0:
- La Partage: you get half your stake back straight away.
- En Prison: your stake is held for the next spin. If that spin wins, you get your stake back (without winnings).
La Partage halves the house edge on even-money bets, from 2.70% to 1.35%, and En Prison brings it down to roughly the same. Neither rule applies to inside bets, dozens or columns. If a table offers one, it's the cheapest way to play roulette. The game's rules or help screen will say whether it applies.
Roulette myths that cost money
"Red is due." The wheel has no memory. After 10 blacks in a row, the chance of red on the next spin is still 18 in 37. Results boards showing recent numbers are there because players like them; they tell you nothing about the next spin.
"Hot and cold numbers." Some numbers will come up more than others in any short run. That's what randomness looks like. On a fair wheel, a hot number is no more likely to come up next.
Betting systems. Doubling up after a loss (the Martingale), raising or lowering stakes in a pattern, or covering most of the table changes how your wins and losses arrive. It can't change the 2.70%, because every single bet inside the system still carries it.
Online and live dealer roulette
Online roulette comes in two forms. In standard online games, a random number generator picks the result, and UK-licensed casinos must have those generators independently tested. In live dealer roulette, you watch a real dealer spin a real wheel on a video stream and place your bets on screen.
The maths in this guide applies to both, as long as you check which wheel you're playing. Variants such as multiplier games change the payouts on straight-up bets to pay for the multipliers, so their edge differs. Always open the game's rules or help screen before you play: it lists the payouts and the return to player.
Roulette questions
What are the odds of winning at roulette?
It depends on the bet. On a European wheel with 37 pockets, a single number wins 1 time in 37 (2.70%), a dozen 12 times in 37 (32.43%) and red or black 18 times in 37 (48.65%). Every one of those bets carries the same 2.70% house edge, because the zero is never paid for.
What is the best bet in roulette?
On a European wheel every bet has the same 2.70% house edge, so the choice changes how often you win and how much, at the same cost. The one cheaper option is an even-money bet at a table with La Partage or En Prison, which cuts the edge to 1.35%. American wheels cost 5.26%.
Is European or American roulette better?
European. It has 37 pockets with a single zero. American roulette adds a double zero to make 38 and keeps the same payouts, which nearly doubles the house edge, from 2.70% to 5.26%. On £1,000 staked, the expected loss is about £27 on a European wheel and £53 on an American one.
Does any betting system work at roulette?
No system changes the house edge. Doubling up after a loss, or any other staking pattern, changes how your wins and losses arrive, and every bet inside the system still carries 2.70% on a European wheel. Over many spins you can expect to lose about that share of everything you stake.
Is online roulette random?
Yes. At UK-licensed casinos, standard online roulette uses a random number generator that has to be independently tested, and live dealer roulette streams a real wheel from a studio. Neither has a memory: after any run of reds, the chance of red on the next spin is still 18 in 37.
Sources and checks
The rules, payouts and quoted figures were last checked against these sources on . Every other number on this page is worked out from those rules, as how we check the numbers explains. If you spot a mistake, our corrections page says how to report it.