How to Play Roulette
In roulette you bet on where a ball will land on a spinning wheel of 37 numbered pockets (0 to 36). You place chips on the table before the spin: on a single number, which pays 35 to 1, or on groups such as red, odd or 1 to 18, which pay less but win more often. When the ball stops, winning bets are paid and losing bets are cleared. There are no decisions after the spin, so the whole game is choosing your bets.
This guide covers the European single-zero wheel, the one used at House21 and in most of the world.
The wheel and the table
The wheel has the numbers 1 to 36, half red and half black, plus one green 0. The numbers aren't in order around the wheel; they alternate red and black and are spread so high, low, odd and even numbers mix evenly.
The table is a grid of the same numbers in three columns of twelve, with the 0 at the top. Around the grid are the boxes for group bets: the three dozens, the three columns, and the six even-money bets (red, black, odd, even, 1 to 18, 19 to 36).
| Color | Numbers |
|---|---|
| Red | 1, 3, 5, 7, 9, 12, 14, 16, 18, 19, 21, 23, 25, 27, 30, 32, 34, 36 |
| Black | 2, 4, 6, 8, 10, 11, 13, 15, 17, 20, 22, 24, 26, 28, 29, 31, 33, 35 |
| Green | 0 |
How a round works
- Place your bets. Put chips on any spots you like, as many as you like, until betting closes.
- No more bets. The wheel spins and the ball is released.
- The ball lands. The winning number is marked on the table.
- Payouts. Each winning bet gets its payout plus the original stake back. Everything else is lost.
At House21 the wheel is shared by everyone online: 20 seconds to bet, an 8-second spin, then 5 seconds of results, so a new round starts about every half minute.
Inside bets: on the numbers
Inside bets go on the number grid itself. They win rarely and pay a lot.
| Bet | How to place it | Numbers covered | Pays | Chance to win |
|---|---|---|---|---|
| Straight up | On one number, including 0 | 1 | 35 to 1 | 2.7% |
| Split | On the line between two numbers | 2 | 17 to 1 | 5.4% |
| Street | At the end of a row of three | 3 | 11 to 1 | 8.1% |
| Corner | Where four numbers meet | 4 | 8 to 1 | 10.8% |
| Six line | At the end of two rows | 6 | 5 to 1 | 16.2% |
House21's table offers straight-up bets on every number; splits, streets, corners and six lines are standard in casinos but not on our table yet.
Outside bets: on groups
Outside bets sit around the grid. They win often and pay less.
| Bet | Covers | Pays | Chance to win |
|---|---|---|---|
| Red or black | 18 numbers | 1 to 1 | 48.6% |
| Odd or even | 18 numbers | 1 to 1 | 48.6% |
| 1 to 18 or 19 to 36 | 18 numbers | 1 to 1 | 48.6% |
| Dozen (1-12, 13-24, 25-36) | 12 numbers | 2 to 1 | 32.4% |
| Column | 12 numbers | 2 to 1 | 32.4% |
The 0 belongs to none of these groups. When the ball lands on 0, every outside bet loses.
What the zero does
Every payout in roulette is set as if the wheel had 36 pockets. A straight-up bet pays 35 to 1, which would be exactly fair with 36 numbers. The 0 is the 37th pocket, and it's where the house makes its money.
On average you lose 1 chip in every 37 you bet, a house edge of 2.70%. That's the same for every bet on a single-zero wheel: no bet has better odds than another in the long run. An American wheel adds a second zero (00) and doubles the edge to 5.26%; our European vs American roulette comparison has the full table.
Worked example
You put 100 chips on red, 50 on the second dozen and 10 on 17 straight up, 160 chips in all. The ball lands on 14 red.
| Bet | Result | You get back |
|---|---|---|
| 100 on red | Wins, pays 1 to 1 | 200 |
| 50 on 13-24 | Wins, pays 2 to 1 | 150 |
| 10 on 17 | Loses | 0 |
| Total | 350 back for 160 bet: +190 |
Had it landed on 0, all three would have lost.
Choosing bets: shape, not odds
Since every bet carries the same 2.70% edge, pick bets by how you want the game to feel:
- Even-money bets keep your stack steady. You win almost half your spins and a session moves slowly.
- Dozens and columns are in between.
- Single numbers mean long dry runs broken by big wins. Bet the same number for 36 spins and about 37% of the time it never comes up.
Betting systems that change your bet size based on previous spins don't change the edge either. We tested six of them on 100,000 sessions each, including the Martingale.
Practical tips
- Set your session size first. With 10,000 chips and 10-chip bets on red, your stack lasts for hundreds of spins. With 1,000-chip bets on a single number, it can be gone in ten.
- Each spin is independent. A number that "hasn't come up" isn't due, and a color that hit five times isn't hot.
- At House21 chips start at 10, with up to 5,000 on one spot and 25,000 in total per spin. Chips are virtual and free.
Common questions
What's the best bet in roulette? On a single-zero wheel they're all equal: every bet returns 97.3% over time. Some French tables return half of even-money bets on a 0 (la partage), which makes those the best bets there.
Is the 0 red or black? Neither. It's green and loses all outside bets.
Can I bet on 0? Yes, as a straight-up bet. It pays 35 to 1 like any other number.
How often does a single number come up? Once every 37 spins on average, but streaks are normal: about 1 time in 15, a given number goes 100 spins without appearing.
Ready to try it? Spin the European wheel on our free roulette page.