The bet that looks even but is not
You are standing at the table, chips in hand, and the layout offers a row of bets that all feel like coin flips: red or black, odd or even, high or low. The odd/even box is the one people reach for when they want something simple. The wheel has 18 odd numbers and 18 even numbers, so on a European wheel that is 36 pockets accounted for. But the wheel does not stop at 36. It has a zero, and on an American layout it has a zero and a double zero. Neither of them is odd or even, and that is the entire answer to the question you typed: 0 and 00 are not included in the odd/even bet, and when either lands, the odd/even wager loses.
This is not a quirk of one table. It is the standard rule across the game, and it is the reason the odd/even bet does not pay at true odds even though it looks balanced. The moment you understand where the zero sits, you understand why the bet is priced the way it is.
How the odd/even bet is settled
The odd/even bet is an outside bet, which means it sits on the outer part of the layout rather than on an individual number. You place your chip in the box marked for odd or for even, and you are wagering that the winning number will belong to that group. The numbers 1, 3, 5 and so on up to 35 are odd. The numbers 2, 4, 6 and so on up to 36 are even. A winning odd/even bet pays 1 to 1: you receive your stake back plus an equal amount in winnings.
Here is the part that surprises new players. The zero pockets are not neutral. They are not a push, and you do not get your stake returned. On almost every standard table, a zero or double zero result means the odd/even bet loses outright, exactly as it would if the wrong colour or the wrong half of the board had come up. A small number of tables in some regions use a rule where an even-money bet is only partially lost or held when zero appears, but that is a specific variant printed on the table rules, not the default. If a table offers it, the layout and the posted rules will say so explicitly.
Why the wheel type changes the price of the bet
The presence of one or two zero pockets is what creates the gap between the payout you receive and the true odds of winning. On a European wheel there are 37 pockets: 18 odd, 18 even, and one zero. On an American wheel there are 38 pockets: 18 odd, 18 even, a zero, and a double zero. The payout is 1 to 1 on both wheels, but the chance of winning is lower on the American layout because there is one extra pocket that belongs to neither group.
This is the clearest way to see it. If the wheel had no zero pockets, an odd/even bet would win 18 times out of 36, which is exactly half the time, and a 1 to 1 payout would be a fair price. The zero pocket means the bet wins 18 times out of 37 on a European wheel, which is slightly less than half. The double zero makes it 18 out of 38 on an American wheel, which is less than half again. The payout does not change to compensate, and that shortfall is the house edge.
| Wheel type | Total pockets | Pockets that win an odd/even bet | Pockets that lose an odd/even bet | Payout on a win |
|---|---|---|---|---|
| European (single zero) | 37 | 18 | 19 (the other parity plus zero) | 1 to 1 |
| American (double zero) | 38 | 18 | 20 (the other parity plus zero and double zero) | 1 to 1 |
The table shows the same bet with two different prices. The American wheel is not a worse bet because the casino is meaner; it is a worse bet because the wheel contains one more pocket that defeats every even-money wager, including odd/even, red/black and high/low. The edge is built into the wheel geometry, not into a hidden rule.
What the zero means for every even-money bet
Odd/even is not alone here. The same logic applies to red/black and to the 1-18 and 19-36 bets. Zero and double zero are typically coloured green on the wheel and the layout, which is the visual cue that they sit outside the red and black groups. They are also outside the high and low groups, because those groups run from 1 to 18 and 19 to 36. Every one of these bets pays 1 to 1 and loses when a zero pocket lands.
This matters because players sometimes move between even-money bets thinking one is safer than another. They are structurally identical on a given wheel. Odd/even, red/black, and high/low all cover 18 winning pockets and lose on the zero or zeros. The house edge is the same for all of them on the same wheel. The choice between them is a matter of preference, not of odds.
Where odd/even sits among the other roulette bets
Roulette offers two broad families of wagers: inside bets, which are placed on individual numbers or small groups of them, and outside bets, which cover large sections of the wheel. Inside bets pay more but win less often. Outside bets pay less but win more often. The odd/even bet belongs to the outside family, and among outside bets it carries one of the lower house edges available on the table.
That does not make it a winning bet. It makes it a bet that loses more slowly than some alternatives. A single-number bet pays 35 to 1 but wins rarely; an odd/even bet pays 1 to 1 and wins nearly half the time. The trade is between the size of the payout and the frequency of winning. The house edge remains on every bet, because every payout is slightly short of what the true odds would require.
| Bet type | What it covers | Payout | How the zero affects it |
|---|---|---|---|
| Odd or even | 18 numbers of one parity | 1 to 1 | Loses on zero and double zero |
| Red or black | 18 numbers of one colour | 1 to 1 | Loses on zero and double zero |
| High or low | 18 numbers in one half of the range | 1 to 1 | Loses on zero and double zero |
| Single number | 1 number | 35 to 1 | Loses unless the number itself is zero |
| Two-number split | 2 adjacent numbers | 17 to 1 | Loses unless a covered number is zero |
The table makes the pattern visible. Outside bets lose to the zero because the zero is not part of their group. Inside bets can include the zero if you place a chip on it or on a split that covers it, but then the zero is simply one more number among the ones you have backed.
The sequence of a round, from buy-in to settlement
Knowing the rule is one thing; sitting down and playing it correctly is another. A round of roulette moves through a fixed sequence, and most procedural mistakes happen because a player acts out of turn or misunderstands what a chip placement means.
You begin by buying in. At a live table, you place cash on the felt and the dealer exchanges it for roulette chips. Roulette chips are often colour-coded per player so that the dealer can tell whose bets are whose when chips sit close together on the layout. You cannot take these chips to another table; you cash them in at the roulette table when you finish.
Once the dealer clears the previous round and announces that betting is open, you place your chips. For an odd/even bet, the chip goes entirely inside the marked box. A chip that straddles a line is a different bet, so place it cleanly. When the dealer calls no more bets, the wheel is already spinning or the ball is in motion. Do not touch the layout after that call.
The ball lands in a numbered pocket, the dealer marks the winning number on the layout, and losing bets are cleared first. Winning bets are then paid. If you placed an odd/even bet and an odd number landed, you are paid 1 to 1. If zero or double zero landed, your chip is swept away with the other losing outside bets.
Mistakes that cost new players at the odd/even box
The first mistake is assuming zero is a push. It is not. A player who believes the bet simply does not count when zero lands will be surprised when the chip disappears. The second mistake is placing the chip so that it touches a line. A chip that overlaps the odd/even box and another bet may be interpreted as a split or as an unclear wager, and the dealer will ask you to clarify or will place it according to house convention. The third mistake is betting after the call of no more bets. Late bets are returned or refused, and repeated late betting can get you removed from the table.
There is also a quieter mistake: moving from odd/even to red/black or high/low in the belief that one of them is due or that switching changes the odds. The wheel has no memory, and all three bets carry the same edge on the same wheel. Switching between them does not change the price you are paying.
What the wheel itself tells you before you bet
Before you sit down, look at the wheel. A European wheel has a single zero; an American wheel has a zero and a double zero. This is visible on the wheel itself and on the layout. Some tables use other regional variants, and the number of zero pockets is the single most important fact about the table, because it determines the edge on every outside bet you are considering.
If the table offers a rule that softens the loss on even-money bets when zero lands, it will be printed on the table or posted nearby. Do not assume it exists. The standard rule is that zero and double zero defeat odd/even, red/black and high/low outright.
FAQ
Do 0 and 00 count as even numbers in roulette?
No. Zero and double zero are not classified as odd or even on a roulette layout. They sit outside the odd/even bet entirely, and when either lands, the odd/even wager loses on a standard table.
Is the odd/even bet the same as red/black?
In terms of structure, yes. Both are even-money outside bets that cover 18 pockets, pay 1 to 1, and lose on zero and double zero. They carry the same house edge on the same wheel, so the choice between them is a matter of preference rather than odds.
What happens to an odd/even bet when zero lands on a European wheel?
On a standard European table, the bet loses outright. The zero pocket is not part of the odd or even group, so a zero result means the odd/even wager is collected along with the other losing outside bets.
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