Two Wheels, Two Different Counts
You are standing at the rail, chips in hand, looking at a spinning wheel. The first thing to know is that not every roulette wheel carries the same number of numbered segments. One layout has 37 pockets; the other has 38. The difference is a single extra pocket, and that pocket changes the arithmetic of every bet you place.
A European-style wheel has 37 numbered segments: the numbers 1 through 36, plus a single zero. An American-style wheel has 38: the same 1 through 36, plus a single zero and a double zero. The numbered sequence is not arranged in numerical order around the wheel. The numbers are distributed in a pattern designed to alternate high and low, odd and even, and red and black as evenly as the wheel's geometry allows.
When someone asks how many numbered segments a spinning roulette wheel has, the honest answer is that it depends on the wheel in front of them. The wheel itself tells you immediately: if you see both a 0 and a 00, you are looking at 38 pockets. If you see only a single 0, you are looking at 37.
What the Extra Pocket Does to Your Bet
The zero pockets are not neutral decoration. They are the house's share of the wheel. On a European wheel, the single zero is the pocket that gives the operator its mathematical advantage. On an American wheel, the double zero adds a second such pocket, which increases that advantage.
Here is the comparison that matters when you choose a table:
| Feature | European-style wheel | American-style wheel |
|---|---|---|
| Numbered segments | 37 | 38 |
| Zero pockets | One (0) | Two (0 and 00) |
| Effect on even-money bets | Lower house edge | Higher house edge |
| Common at | Many venues outside the United States, and some US tables | Many venues in the United States |
The extra pocket does not change how the game is played. It changes how often a bet that pays even money loses. A bet on red, black, odd, even, high or low loses when the ball lands in any zero pocket. With one zero, there is one such losing pocket. With two, there are two. That is the entire difference, and it is enough to make the American layout the more expensive game over a long session.
House edge and return to player are complements: for the same bet under the same rule set, they sum to 100%. The edge is the operator's long-run share of each wager. It is not a forecast of your next spin, and it does not mean you will lose exactly that percentage in an hour. It is the rate at which the game grinds, and the wheel with the extra pocket grinds faster.
From Buy-In to Settlement: How a Round Moves
The wheel's pocket count is one part of sitting down correctly. The other part is knowing the sequence of a round, because the wheel spins on a fixed rhythm and your decisions all happen before the ball is released.
You buy in at the table, not from a machine. You place cash on the felt, and the dealer exchanges it for roulette chips. These chips are often colour-coded to you alone at that table. They have no value away from the wheel, so you cash them in at the same table before you leave.
A round moves through four stages. First, the dealer opens betting. You place chips on the layout, and you may place several bets at once: a straight-up number, a split across two numbers, a column, an even-money outside bet. Second, the dealer sends the ball around the wheel in the opposite direction to the wheel's spin. Third, the ball drops into a pocket. The dealer marks the winning number on the layout and clears losing bets. Fourth, winning bets are paid, and the next round opens.
The decision point is entirely front-loaded. Once the ball is moving, you cannot change your bet. Everything you decide happens while the layout is open and the wheel is still or just beginning to turn.
The Bet Types and Why They Cost Different Amounts
Roulette looks like one game, but it is really a family of bets with materially different edges. The wheel's pocket count applies to all of them, but the payout structure differs by bet type, and so does the long-run cost.
Inside bets sit on the numbered grid. A straight-up bet on a single number pays the most but hits least often. A split covers two numbers, a street covers three, a corner covers four, and a six-line covers six. Outside bets sit around the grid and cover larger groups: red or black, odd or even, high or low, dozens, and columns. The outside even-money bets lose on any zero pocket, which is why the wheel's zero count matters so directly to them.
| Bet type | What it covers | Payout shape | How the zeros affect it |
|---|---|---|---|
| Straight-up | One number | Largest single payout | Loses unless the number hits |
| Split | Two adjacent numbers | Half the straight-up payout | Loses unless one of the two hits |
| Street | Three numbers in a row | Lower than split | Loses unless one of the three hits |
| Even-money outside | Red, black, odd, even, high, low | 1 to 1 | Loses on any zero pocket |
| Dozen or column | Twelve numbers | 2 to 1 | Loses on any zero pocket |
The table does not display a house edge. It displays payouts. The edge is built into the gap between the payout and the true odds of the bet. A straight-up number on a 37-pocket wheel pays as if there were 36 numbers, and that missing unit is the house's share. On a 38-pocket wheel, the same bet pays as if there were still 36, so the gap is wider.
No betting pattern changes that structure. Covering more numbers changes how often you win and how much you receive when you do, but it does not remove the built-in edge. A player who spreads chips across the layout is buying a different distribution of outcomes, not a better one.
What Strategy Means at a Roulette Table
Roulette is not a comparing game like blackjack, where a decision chart derives from a specific rule set. There is no decision to make about hitting or standing. The only decisions are which bets to place, how much to stake, and when to stop. Those choices change the variance of a session, not the long-run edge.
That does not make the choices meaningless. A player who wants a long, low-variance session can favour outside bets, accepting smaller payouts in exchange for more frequent wins. A player who wants a short, high-variance session can favour inside bets, accepting longer dry spells in exchange for the chance of a larger single payout. Neither approach changes the wheel's arithmetic. Both are legitimate ways to spend an evening, provided the player understands that the edge stays with the house on every spin.
Volatility is the term for how payouts are distributed over time. High volatility means rarer but larger payouts; low volatility means more frequent but smaller ones. Volatility does not change a game's RTP. A high-volatility approach at roulette does not become a better bet because the wins are bigger; it becomes a streakier one.
Procedural Mistakes That Cost New Players
The wheel's pocket count is the first thing to check, but it is not the only thing that separates a smooth session from a frustrating one. New players tend to make the same three procedural errors, and none of them involve the spin itself.
The first is treating roulette chips as cash. The coloured chips you receive at the table are not interchangeable with the chips at another table, and they cannot be carried to the cashier. They must be converted back at the roulette table where they were issued. A player who walks away with a pocketful of coloured chips has not walked away with money.
The second is betting after the dealer has closed the layout. Once the ball is released, or once the dealer calls no more bets, any chip placed on the felt is late. Late bets are returned, and repeated late betting will draw the dealer's attention. The entire decision window is before the spin.
The third is misreading the zero pockets as a side bet. They are not. They are losing pockets for every outside bet and every inside bet that does not include them. A player who wants to cover the zero must place a bet on it directly, and that bet carries the same house edge as any other straight-up number.
Before you sit down, read the table. The wheel shows you its pocket count. The layout shows you the minimum and maximum stakes. The felt shows you the payout schedule. Those three pieces of information tell you everything about the game you are about to play, and none of them require you to ask anyone a question.
FAQ
Why do some roulette wheels have 37 pockets and others 38?
The difference is the double zero. A European-style layout has a single zero alongside the numbers 1 through 36, for 37 pockets. An American-style layout adds a double zero, for 38. The extra pocket increases the house edge on every bet, because it is an additional losing pocket for bets that do not cover it.
Does the number of pockets change how the game pays?
The payout schedule is the same on both wheels. A straight-up number pays the same multiple on a 37-pocket wheel as on a 38-pocket wheel. What changes is the true odds of any bet, because the ball has one more pocket to land in on the American layout. The payout stays fixed while the probability shifts, and that is where the extra edge comes from.
Can I tell which wheel I am playing just by looking?
Yes. Look at the wheel itself, not the layout. If you see a single zero pocket, it is a 37-pocket wheel. If you see both a 0 and a 00, it is a 38-pocket wheel. The layout will also show the zeros, but the wheel is the fastest check, and it is visible from across the table before you sit down.
Gamble responsibly. If you or someone you know has a gambling problem, call the helpline printed in the footer below.
Play responsibly
Gambling should be treated as paid entertainment, never as a way to earn income or recover losses. 1-800-MY-RESET (1-800-697-3738)
18+ or 21+ depending on where you are; follow the minimum age that applies to you.
This article is general information about how these mechanics work. It is not legal advice and not a recommendation to gamble or to use any particular operator. Availability and legality differ by jurisdiction — check the rules that apply where you are.