The Extra Pocket That Changes the Odds
A roulette wheel with two green pockets marked 0 and 00 is an American wheel. The second green pocket is called the double zero, and it is the single biggest reason the same bet can cost you more on one table than on another. A European wheel has 37 pockets: the numbers 1 through 36 plus a single zero. An American wheel has 38: the same 36 numbers, a single zero, and the double zero. That one additional pocket is not a cosmetic difference. It changes the arithmetic of every wager placed on the layout.
When a player asks what double zeros are called, the honest answer is that the term is simply "double zero" or "00." The more useful question is what the pocket does. Every pocket on the wheel is a possible resting place for the ball. When the ball lands in 0 or 00, most outside bets lose, and the house collects. The extra pocket adds one more losing outcome to the wheel without adding any new winning outcomes for the player. That is where the house edge comes from.
American and European Wheels Side by Side
The two wheel types are the most common layouts a player will encounter. The difference is structural, not cosmetic: the number of pockets, the order of numbers around the wheel, and the edge on most bets all change. A player who sits down at a table should identify the wheel type before placing a single chip, because the same bet does not carry the same expected loss on both wheels.
| Feature | European wheel | American wheel |
|---|---|---|
| Pockets | 37 | 38 |
| Zero pockets | One (0) | Two (0 and 00) |
| Number range | 0-36 | 0, 00, 1-36 |
| Effect on outside bets | Zero loses most outside bets | Both zeros lose most outside bets |
| House edge on most bets | Lower | Higher |
The table shows the structural facts. The exact house edge on any given bet is printed in the game information panel or the operator's rules page for the specific table in use, and a player should read that figure rather than rely on memory. The direction of the difference, however, is fixed: the double zero adds a losing pocket, and that raises the cost of playing.
What the Double Zero Does to a Bet
Consider a straight-up bet on a single number. On a European wheel, the bet wins if the ball lands in that one pocket out of 37. On an American wheel, the same bet wins if the ball lands in that one pocket out of 38. The payout for a winning straight-up bet is the same on both wheels, but the probability of winning is lower on the American layout. The player is paid as though the wheel had fewer pockets than it does. That gap between the payout and the true odds is the house edge.
The same logic applies to outside bets. A bet on red loses when the ball lands in any black pocket, but it also loses on 0 and 00. On a European wheel, the zero is the only green pocket that defeats the bet. On an American wheel, both green pockets defeat it. The player has not gained any new winning pockets; the house has gained a new losing one.
Why the Double Zero Exists
The double zero is a historical feature of the game's development in North America. Early roulette wheels in the United States were built with two zero pockets, and the layout persisted as the standard American format. The extra pocket was not added to change the game's fairness in any hidden way; it is simply a different wheel configuration. The effect, however, is exactly what a player should expect: more pockets mean fewer winning outcomes for the same wager.
Some American tables also use a rule that changes how even-money outside bets lose when a zero appears, but that rule varies by venue and by table. A player should check the posted table rules before assuming any special treatment applies. The presence of the double zero is a fixed feature of the wheel; the rules attached to it are not.
Reading the Layout Before You Play
The first step at any roulette table is to look at the wheel itself. Count the green pockets. If there are two, the table is American, and the double zero is in play. The layout will also show the 00 betting space next to the 0 at the head of the number grid. A player who sits down without checking this has not yet understood the game they are about to play.
The second step is to check the posted table minimums and maximums, and the third is to read the game information panel for the specific house edge and payout schedule. Roulette payouts are standard across most tables, but the rules governing zero behaviour, special bets, and maximum stakes are not. The double zero changes the odds; the table rules determine how much of that change reaches the player's bankroll.
How the Double Zero Affects Different Bets
Not every bet on the layout is affected equally by the double zero. Inside bets, outside bets, and the zero bets themselves all interact with the extra pocket in different ways. The table below separates the main bet categories and what the double zero does to each.
| Bet type | What it covers | Effect of the double zero |
|---|---|---|
| Straight-up | One number | One extra losing pocket out of 38 |
| Split | Two adjacent numbers | Same extra losing pocket |
| Street | Three numbers in a row | Same extra losing pocket |
| Red/black | All red or all black numbers | Both zeros lose the bet |
| Odd/even | All odd or all even numbers | Both zeros lose the bet |
| High/low | 1-18 or 19-36 | Both zeros lose the bet |
| Zero bet | 0 or 00 individually | 00 becomes an additional wagerable pocket |
The table shows the mechanical effect. The house edge on each bet is a separate figure, and it is not uniform across the layout. A player who wants the exact number for a specific bet should consult the game information panel for the table in use, because rule variations can shift the figure slightly even between two American wheels.
The Sequence of a Round
A round of roulette moves through a fixed sequence, and the double zero is present at every stage. The dealer opens betting, players place chips on the layout, the dealer closes betting, the ball is spun in the opposite direction of the wheel, the ball drops into a pocket, and the dealer settles winning and losing bets. The double zero is simply one of the pockets the ball can land in.
New players sometimes place a bet after the dealer has called no more bets, or they reach toward the layout while the ball is still spinning. Both are procedural mistakes that slow the table and can void a bet. The correct moment to place a chip is during the open betting window, before the dealer closes the round. The double zero does not change this sequence; it only changes the odds of the outcome.
Deciding Where to Sit
A player who has a choice between an American and a European wheel faces a decision that is entirely about expected loss. The European wheel has fewer pockets, which means the same bet loses less often over a large number of spins. The American wheel has the double zero, which means the same bet loses more often. No betting pattern changes this. A player can choose the wheel, the bet, and the stake, but the edge is built into the wheel itself.
That does not mean an American table is somehow defective. It means the player is paying more per wager for the same game. The choice is a matter of what the player values: the availability of the table, the atmosphere, the specific rules, or the lower expected loss of the single-zero layout. A player who understands the double zero can make that choice with open eyes.
FAQ
Is 00 the same as 0 in roulette?
No. They are separate pockets on the wheel and separate betting spaces on the layout. On an American wheel, 0 and 00 are both green pockets, but they are distinct outcomes. A bet on 0 does not win when the ball lands in 00, and vice versa.
Why does American roulette have two zeros?
The double zero is a historical feature of the American wheel layout. Early wheels in the United States were built with two zero pockets, and the configuration became the standard American format. The extra pocket increases the house edge on most bets compared with a single-zero wheel.
Can I avoid the double zero by betting differently?
No bet on an American wheel removes the double zero from the wheel. The pocket is always a possible outcome. A player can choose a European wheel with a single zero, or they can choose bets with different edges, but the double zero remains part of the American game on every spin.
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