The green pocket sits outside the even-odd split
A roulette wheel does not treat zero as a number like the others. The even and odd bets split the numbers 1 through 36 into two groups of eighteen, and zero is deliberately left out of both. When the ball lands in the zero pocket, an even-money bet on even or on odd is a losing bet on the standard layouts. The zero is green, not red or black, and that colour separation is the table's way of telling you the pocket belongs to neither side of the outside bets.
This matters more than a beginner expects, because the zero is the single pocket that most quietly changes the arithmetic of the whole table. The even and odd bets look like a coin flip: eighteen winning numbers against eighteen losing numbers. But the wheel has a thirty-seventh pocket on a European layout and a thirty-eighth on an American one. Those extra green pockets are why the bet does not pay at true odds, and why the zero is not just a curiosity but the mechanism through which the house keeps its edge on the outside bets.
How the even and odd bets work
An even-money bet in roulette pays one unit for every unit wagered. If you place a wager on even, you win when the ball settles on any even number from the 1-36 range, and you lose when it settles on any odd number. The same logic runs in reverse for the odd bet. The zero is the exception that breaks the symmetry: it is not an even number for betting purposes, it is not an odd number, and it does not pay out on either wager.
The table layout makes this visible. The even and odd betting boxes sit among the outside bets, and the zero has its own box at the end of the layout. On a European single-zero table, the zero box usually sits at the top of the column of numbers. On an American double-zero table, both the 0 and the 00 have their own boxes. A player who wants to cover the zero has to bet on it directly, or place a broader wager that includes it.
What the zero does to the odds
A European wheel has 37 pockets, and the even bet covers 18 of them. The remaining 19 pockets lose the bet: the 18 odd numbers plus the single zero. That one extra losing pocket is the entire source of the house edge on the even-money bets under the standard European rule set. The same structure applies to red and black, and to the high and low bets. On an American wheel the effect is larger, because the 00 pocket adds a second green number that loses on all of those outside bets.
House edge and RTP are complements: for the same bet under the same rule set they sum to 100%. The even-money bets on a European wheel carry a lower house edge than the same bets on an American wheel, because the American layout has one more pocket that loses without adding any winning numbers. The difference between the two wheels is not a small design detail; it changes the expected rate of loss on every outside bet a player makes.
| Wheel type | Pockets | Green pockets | Even bet covers | Pockets that lose the even bet |
|---|---|---|---|---|
| European | 37 | 1 (single zero) | 18 even numbers | 19 (18 odd plus zero) |
| American | 38 | 2 (0 and 00) | 18 even numbers | 20 (18 odd plus both zeros) |
The table shows why the green pocket is not a side issue. On a European wheel the even bet loses on 19 pockets and wins on 18, which is the gap that keeps the bet below a true 50-50 proposition. On an American wheel the gap widens to 20 losing pockets against 18 winning ones. The zero does not just sit outside the even-odd split; it is the pocket that makes the split unfair to the player in the long run.
Some tables soften the zero, and the rule has a name
A minority of European tables offer a rule that changes what happens when the zero lands on an even-money bet. Under that rule, sometimes called "la partage" or "en prison", the player does not lose the whole wager immediately. The specifics differ by venue: one version returns half the stake, and another holds the stake in place for the next spin and returns it only if the following spin wins. Both versions reduce the house edge on the even-money bets compared with a standard European table where the zero simply loses.
This rule is not universal, and it is not something to assume. The table's posted rules state whether the zero loses outright on even-money bets or whether a partage or prison rule applies. A player who cares about the difference should read the felt or the game information panel before the first spin. The rule changes the expected rate of loss on the outside bets, but it does not turn the zero into an even or odd number: the pocket still pays neither bet.
Betting the zero directly
The zero can be bet on its own, or as part of a group of numbers. A straight-up bet on the zero pays at the table's posted odds for a single number, which are materially higher than the even-money payout because the bet covers only one pocket. The zero can also be included in split bets, street bets, or the broader outside wagers that cover sections of the wheel, depending on the layout. On an American table the 0 and 00 can be bet together as a pair, and the payout for that pair reflects the fact that it covers two pockets out of thirty-eight.
None of this changes the answer to the original question. The zero is not even, it is not odd, and it does not belong to either outside bet. It is a separate pocket with its own box, its own colour, and its own payout schedule. The moment a player understands that, the structure of the whole table becomes easier to read: the outside bets cover the numbered pockets in clean halves, and the green pockets are the house's share of the wheel.
Where new players go wrong
The most common mistake is assuming the zero behaves like a regular number. A player who has bet on even and sees the ball land in the zero pocket sometimes expects the bet to push or to be returned, because zero feels like it should be an even number in ordinary arithmetic. In casino roulette it is not. The bet loses unless the specific table rule says otherwise, and the croupier will sweep the losing outside bets exactly as if an odd number had landed.
A second mistake is treating the even and odd bets as a coin flip and sizing them accordingly. The zero is the reason the bet is not a coin flip. The payout is even money, but the probability of winning is slightly below half on a European wheel and further below half on an American one. That gap is small on any single spin, and over many spins it is the difference between a bet that roughly breaks even and a bet that steadily loses at the table's built-in rate.
A third mistake is chasing the zero after it has appeared. The wheel has no memory, and the zero is not due, hot, or overdue. Each spin is an independent event under a properly functioning random number generator or physical wheel, and the probability of the zero landing on the next spin is the same as it was on the previous one. No betting pattern changes the built-in edge of a negative-expectation game, and progression systems that double after losses redistribute outcomes rather than remove the edge.
Reading the table before you sit down
Every roulette table states its own rules on the felt or on a nearby information panel. The things to check before playing are the wheel type, the minimum and maximum stakes for inside and outside bets, and whether any special rule applies to the zero on even-money wagers. Those three details determine more about the session than any betting system a player might bring to the table. A European wheel with a partage rule is a different game from an American wheel where both green pockets lose outright, and the difference shows up in the expected rate of loss on every outside bet.
The zero is the clearest single example of how a roulette table's rules sit in the layout itself. The colour, the box, and the payout all tell the same story: the zero is outside the even-odd split, outside the red-black split, and outside the high-low split. It is the pocket the house keeps, and understanding that is the first step to reading any roulette table correctly.
FAQ
Does 0 count as even in roulette for betting purposes?
No. The even bet covers only the even numbers from 1 to 36. The zero pocket is green and sits outside the even and odd betting boxes, so a wager on even loses when the zero lands on a standard table.
What happens to an even-money bet when the ball lands on 0?
On most tables the bet loses outright. A minority of European tables apply a partage or en prison rule that returns half the stake or holds it for the next spin, but that rule must be stated on the table or in the game information panel. It is never safe to assume it applies.
Is the 00 treated the same as the 0 on an American wheel?
Yes. Both green pockets sit outside the even and odd bets, and both lose on even-money outside wagers. The American wheel has two green pockets, which is why the even-money bets carry a higher house edge on that layout than on a single-zero European wheel.
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