Roulette is one of the most recognisable casino games, but the green zero often causes confusion. It might look like just another number, yet it plays a special role that changes how the game works.
This guide explains what the zero represents, how it can affect betting options such as even and odd, and why it gives the casino an advantage. Understanding this single pocket can help you make sense of the rules, the odds, and the difference between European, American, and French roulette.
Is 0 an Even Number in Roulette?
Mathematically, zero is classed as an even number because it can be divided by two without a remainder. In roulette, however, it’s treated differently.
A European roulette wheel contains 37 pockets — numbers 1 to 36 plus a single green 0. An American wheel has 38 pockets, with an extra green 00.
When you bet on “even” or “odd”, you’re only betting on numbers between 1 and 36. The green zero does not belong to either group, so if the ball lands there, these bets lose.
Some versions, such as French roulette, include rules that may help lessen this loss:
- La partage – half of your even-money stake is returned if the ball lands on 0.
- En prison – your even-money bet stays on the table for the next spin; if it wins then, your stake is returned.
These rules don’t make zero even or odd, but they slightly reduce the casino’s advantage on those bets.
How Does Zero Affect Even Money Bets?
Even-money bets pay 1 to 1, meaning you win the same amount as your stake. These include:
- Red or black – the colour of the winning number
- Even or odd – the number’s classification
- 1–18 or 19–36 – whether the number is in the lower or higher half
Each covers 18 possible numbers. However, because the European wheel has 37 pockets, your chance of winning is 18/37, or about 48.65%.
On an American wheel, there are 38 pockets in total, and 18 of them win on an even-money bet. This means your chance of winning is 18 out of 38, or about 47.37%. The remaining percentage comes from the two green pockets — 0 and 00 — which give the casino its built-in advantage.
If 0 or 00 appears, these bets lose, unless a rule like la partage or en prison applies. Where they do, the house edge on even-money bets drops to around 1.35%. Without these rules, it’s 2.70% on European wheels and 5.26% on American ones.
The Role of 0 in European vs American Roulette
The green zero separates European and American roulette. A European wheel has one zero and 36 red and black numbers, producing a house edge of about 2.70%. An American wheel has both 0 and 00, raising the house edge to around 5.26%.
That small difference has a major effect over time. The potential payouts on both wheels are the same, but the extra green pocket in American roulette slightly reduces the likelihood of winning bets.
The order of numbers on each wheel also differs, changing how some players arrange their bets. However, roulette is a random game of chance — each spin is independent, and no pattern or system can predict or influence results.
Before placing any wagers, it can be useful to read the paytable or rules section for the specific roulette table. This explains which version you’re playing, how bets are settled, and whether any special rules apply.
Does 0 Count as Red or Black?
Zero is green on all roulette wheels, marking it apart from the red and black numbers. In American roulette, the double zero is also green.
If you bet on red or black and the ball lands on 0 or 00, your wager loses unless la partage or en prison applies. The green pocket’s purpose is to give the casino its built-in advantage by sitting outside all colour and even-money bets.
House Edge and the Impact of Zero
The house edge is the percentage that represents the casino’s long-term profit. In roulette, it comes from the green zero pockets being excluded from most outside bets.
- European roulette (single zero) – edge of around 2.70%
- American roulette (0 and 00) – edge of around 5.26%
- French roulette with la partage – edge of around 1.35% on even-money bets
For example, if you wager £10 on red in European roulette, your chance of winning is about 48.65%. That small gap between payout potential and probability is what gives the casino its consistent edge over many spins.
No betting system can remove this advantage. Roulette outcomes are random, and each spin is independent. Managing how much you spend and setting sensible limits can help you keep play responsible.
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