The Count That Starts the Question
You are standing at a roulette table, chips in hand, and you want to know whether to put them on even or on something else. The first thing to know is that the wheel contains 18 even numbers and 18 odd numbers. That symmetry is deliberate, and it is the reason the even-money bets exist at all. But the wheel also contains pockets that are neither even nor odd, and those pockets are where the operator's advantage lives.
The numbers on a roulette wheel run from 0 to 36. On a European wheel, that means 37 pockets: the numbers 1 through 36, plus a single zero. On an American wheel, there are 38 pockets: the same 1 through 36, plus a single zero and a double zero. In both layouts, the numbers 1 through 36 split exactly in half between evens and odds. That gives you 18 even numbers and 18 odd numbers. The zero, and the double zero where present, sit outside that split.
This matters because the even-money bet on roulette is not a coin flip. A coin has two sides and no house pocket. A roulette wheel has the even numbers, the odd numbers, and at least one green pocket that belongs to neither group. When you bet on even, you are betting on 18 of the 37 or 38 possible outcomes. When the ball lands in zero, your even bet loses, and that is the entire mechanism by which the house edge operates on this wager.
What the Even-Money Bet Covers
On a roulette layout, the even-money bets are the outside bets that pay 1 to 1. They are called even-money because a winning wager returns your stake plus an equal amount in profit. The three standard pairs are red or black, high or low, and even or odd. The even bet covers every even number from 2 through 36. The odd bet covers every odd number from 1 through 35.
What the even bet does not cover is just as important as what it does. The zero and double zero are not even numbers. They are not odd numbers either. They are not red or black in the sense that matters for the red/black bet, and they are not high or low in the sense that matters for the high/low bet. On most layouts, the zeros are green and sit at the top of the number column. A ball landing in a zero pocket loses every even-money bet on the table, unless the table rules include a special provision for the zero.
Some European tables offer a rule called la partage or en prison. Under these rules, when the ball lands in zero, an even-money bet is not collected immediately. Instead, half the stake is returned to the player, or the whole stake is held in place for the next spin. These rules reduce the house edge on even-money bets because they soften the loss on the zero. They are table-specific, so you should check the posted rules before you sit down.
How the Wheel Layout Distributes Evens and Odds
The sequence of numbers around the wheel is not a simple alternating pattern of even and odd. The arrangement is designed to scatter high and low numbers, red and black, and even and odd around the circumference. This is a physical design choice, not a mathematical one. The wheel would function identically in terms of probability if the numbers were arranged in numerical order. The scattering exists to make the wheel feel balanced and to prevent any obvious visual clustering.
Because the sequence is scattered, you cannot predict the next number by looking at where the ball is about to land relative to the even numbers. The ball does not know what the last number was, and the wheel does not remember it. Each spin is an independent event under a properly functioning random number generator or a properly balanced physical wheel. The 18 even numbers are always 18 of the 37 or 38 possible outcomes, no matter what happened on the previous spin.
Here is the comparison between the two main wheel types and what the even bet means on each:
| Feature | European wheel | American wheel |
|---|---|---|
| Total pockets | 37 | 38 |
| Zero pockets | 1 (single zero) | 2 (single and double zero) |
| Even numbers | 18 | 18 |
| Odd numbers | 18 | 18 |
| Even bet winning pockets | 18 of 37 | 18 of 38 |
| Even bet losing pockets | 19 (18 odd plus zero) | 20 (18 odd plus two zeros) |
The table shows the structural difference clearly. The even numbers are identical in count across both wheels. What changes is the number of losing pockets. The American wheel adds one more pocket that defeats the even bet, and that single extra pocket is enough to make the even-money wager worse on the American layout.
Why 18 Even Numbers Do Not Mean a 50% Chance
A common misreading is to see 18 even numbers and 18 odd numbers and conclude that an even-money bet has a 50% chance of winning. That conclusion ignores the zero. On a European wheel, the even bet wins on 18 pockets and loses on 19. The probability of winning is 18 divided by 37, which is less than half. On an American wheel, the probability is 18 divided by 38, which is lower still.
The house edge is the complement of the return to player, and both are long-run statistical averages. For the even-money bet, the edge comes entirely from the zero pockets. No amount of bet selection among the even-money options changes this. Red, black, even, odd, high and low all face the same zero exposure on a given wheel. The only thing that changes the edge is the wheel type and any special zero rule the table applies.
What this means in practical terms is that the even bet is a negative-expectation wager, like every other bet on the table. It is one of the lower-edge bets available on a roulette layout, but it is not a break-even proposition. The zero is always there, taking a small slice of the long-run return. You can reduce the size of that slice by choosing a European wheel over an American one, or by finding a table with a zero rule that returns part of the stake. You cannot remove it.
How a Round Plays Out from Buy-In to Settlement
You buy in at the table by placing cash on the layout. The dealer exchanges it for roulette chips, which are typically a distinct colour so that each player's chips are identifiable. You then place your bets on the layout before the dealer calls for no more bets. On the even bet, you place your chips on the box marked even, or on the section of the layout that carries that label.
The dealer spins the wheel in one direction and sends the ball travelling in the opposite direction. Once the ball drops into a pocket, the dealer marks the winning number on the layout. Losing bets are collected first. Winning bets are then paid. An even-money bet pays 1 to 1, so a winning wager of ten units returns ten units in profit plus the original ten units. A losing wager is simply collected.
The sequence has no decision points after the spin begins. Roulette is not a game of strategy in the way blackjack is. Your only decisions are which bets to place, how much to stake, and when to stop. That makes the even bet simple to play and simple to misread. The simplicity of the bet does not change the mathematics underneath it.
Where New Players Go Wrong
The first procedural mistake is assuming that the zero is an even number or that it somehow counts as a win for the even bet. It is not and it does not. The zero is a separate pocket that loses every even-money bet unless the table has a special zero rule. A player who has not read the layout carefully can be surprised when a green zero appears and their even bet is swept away.
The second mistake is treating the even bet as a coin flip and staking it accordingly. The bet feels close to 50/50, and over a short session it can behave like one. But the zero is always present, and over enough spins the house edge expresses itself. Players who size their bets as if the wager were a true 50/50 proposition are staking against a probability that is slightly worse than they believe.
The third mistake is switching between even-money bets in the belief that one is due. A player who has seen five reds in a row may switch to black, or a player who has seen several odds may switch to even. The wheel has no memory. The probability of an even number on the next spin is the same as it was on the previous spin, regardless of the sequence that came before. No pattern of past results changes the count of even pockets on the wheel.
What the Even Count Tells You About the Rest of the Table
The even bet is one of several outside bets on the layout. Alongside even and odd sit red and black, high and low, dozens, and columns. Each of these bets has its own payout and its own house edge, and they are not all equal. The even-money bets share the same edge on a given wheel, but the dozens and columns pay 2 to 1 and carry a different risk profile. The inside bets on individual numbers pay 35 to 1 and carry a materially different edge.
Here is how the main bet groups compare on a European wheel, using the structure of the wheel rather than invented percentages:
| Bet type | Pockets covered | Payout | How the zero affects it |
|---|---|---|---|
| Even-money (even, odd, red, black, high, low) | 18 of 37 | 1 to 1 | Loses on zero unless a special rule applies |
| Dozen or column | 12 of 37 | 2 to 1 | Loses on zero |
| Six-line | 6 of 37 | 5 to 1 | Loses on zero |
| Single number | 1 of 37 | 35 to 1 | Loses on zero |
The table shows the trade-off. The even bet covers the most pockets and pays the least. The single number covers the fewest pockets and pays the most. The zero is a losing pocket for every bet on the table, which is why it is the source of the house edge across the whole layout. No bet escapes it.
FAQ
Is zero considered an even number in roulette?
No. The zero is not even and not odd. It is a separate pocket that loses every even-money bet unless the table rules include a special provision such as la partage or en prison. The even bet covers only the 18 even numbers from 2 through 36.
How many odd numbers are on a roulette wheel?
There are 18 odd numbers on both European and American wheels, matching the 18 even numbers. The numbers 1 through 36 split exactly in half between even and odd. The zero pockets sit outside both groups.
Does betting on even give you better odds than betting on a single number?
The even bet covers 18 of the 37 or 38 pockets and pays 1 to 1, while a single number covers one pocket and pays 35 to 1. The even bet wins more often but pays less. Both bets carry a house edge because the zero pockets are losing outcomes for both.
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