An odd/even bet is a roulette outside bet on number parity. You choose whether the winning number will be odd or even. It pays even money when correct, but zero and double zero are neither odd nor even for betting purposes, so they usually make the bet lose.
Plain Talk
Odd/even is the number-version of red/black. Instead of betting on color, you are betting on whether the result is odd or even from 1 through 36.
The trick is simple: roulette zero is not counted as even in this bet. It is a house pocket. On American roulette, double zero is another house pocket.
| Term | Plain-English meaning | Where it appears | Why it matters |
|---|---|---|---|
| Odd Bet | Bet on odd numbers | Outside layout | Wins on 1, 3, 5, and so on |
| Even Bet | Bet on even numbers | Outside layout | Wins on 2, 4, 6, and so on |
| Zero | Neither odd nor even here | Green pocket | Makes the bet lose |
| Even money | 1:1 payout | Payout rules | Does not mean fair odds |
Where You See It
Odd and even betting boxes sit in the outside section of the roulette layout. You see them near red/black and high/low bets.
Published roulette rules from Wizard of Odds and the Nevada Gaming Control Board single-zero roulette rules of play describe a wheel with numbered pockets where outside bets are resolved after the dealer calls no more bets. Casino rule pages such as Venetian roulette rules also list odd/even among the even-money betting choices.
Why It Matters
Odd/even matters because it is one of the easiest roulette bets to understand and one of the easiest to misread. Players hear “even” and think zero should count. It does not.
The bet covers 18 numbers. On a single-zero wheel, that leaves 19 losing results. On a double-zero wheel, it leaves 20 losing results.
Example
You bet $10 on odd.
If the ball lands on 17, you win $10. If it lands on 22, zero, or double zero, you lose.
A player who says, “Zero is even, so I should win,” is using ordinary math language, not casino bet language. On the roulette layout, zero is outside the odd/even groups.
From the Casino Side:
From the casino side, odd/even is a standard outside wager. It is easy for dealers to settle, easy for surveillance to review, and easy for players to understand visually.
Management does not view odd/even as a special strategy area. It is part of the same roulette hold structure as other standard even-money bets.
Common Misunderstanding
The biggest misunderstanding is believing even means “all even-looking outcomes.” In roulette betting, even means the numbered even results from 2 through 36 only.
The second mistake is using streaks. Ten odd results do not make even more likely on the next spin.
Hard Truth
Hard Truth: Odd and even are not a secret rhythm in the wheel. They are two large losing propositions with a clean label.
Related Terms
FAQ
Does zero count as even in roulette?
No. Zero is not part of the even bet.
What does odd/even pay?
A winning odd/even bet normally pays 1:1.
Is odd/even better than red/black?
No. On the same wheel type, the math is effectively the same.
Can odd/even be used to beat roulette?
No. Betting odd after many even results is still a guess against the house edge.
Does La Partage help odd/even?
Yes, if the table applies La Partage to even-money bets, it can reduce the loss when zero appears.
Deeper Insight
Odd/even is a good example of casino language having its own exact meaning. In ordinary math, zero has special properties. In roulette betting, zero is a separate green result that does not belong to odd, even, red, black, high, or low.
For deeper player behavior, read Gambler’s Fallacy and Ask a Veteran. For the full game, read Roulette.
Formula / Calculation
| Wheel type | Winning numbers | Losing results | Expected value on $1 |
|---|---|---|---|
| European roulette | 18 | 19 | (18/37 × $1) - (19/37 × $1) = -$0.0270 |
| American roulette | 18 | 20 | (18/38 × $1) - (20/38 × $1) = -$0.0526 |
Expected Loss = Total Amount Wagered × House Edge
Formula Explanation in Plain English
The odd/even bet wins on 18 numbers. It loses on the opposite 18 numbers plus zero. American roulette adds double zero, which increases the number of losing outcomes.
Related Reading
Start with Roulette for the game layout, then read Outside Bet and Even Money Bet. For zero-specific rules, continue with Zero and Double Zero. If roulette is becoming hard to stop, use safer-play tools described by the UK Gambling Commission.