You are looking at an American wheel
A wheel with 38 numbered slots is not the only kind of roulette wheel, and the difference matters before you place a single chip. The 38-slot layout is the American configuration: the numbers 1 through 36, a single zero, and a double zero. The other common wheel, the European layout, carries 37 slots because it has only the single zero. That one extra pocket is not a cosmetic detail. It changes the arithmetic on every bet you can make.
Roulette is a game of pure chance. No decision you make after the ball is released alters where it lands. What you do control is which wheel you sit at, which bets you place, and how much of your session bankroll each bet consumes. This article walks through a round from buy-in to settlement, explains each bet type on a 38-slot wheel, and shows why the double zero is the first thing a new player should notice.
The object and the layout
The object is simple: predict which numbered slot the ball will settle into. The wheel has 38 pockets, each colored red or black except the zero and double zero, which are green. The table layout mirrors the wheel. You place chips on the layout to indicate your prediction, the dealer releases the ball against the wheel's spin, and when the ball drops into a pocket the dealer marks the winning number and settles all bets.
Because a roulette wheel has 38 numbered slots on the American layout, each individual number has a 1-in-38 chance of appearing on any spin, assuming a fair wheel. That probability is fixed. It does not remember what came before. A number that has not appeared for fifty spins is no more likely to appear on the fifty-first than any other number. The wheel has no memory, and no betting pattern changes the underlying probabilities.
From buy-in to settlement
You cannot bet with regular casino chips at the roulette table. When you sit down, place your cash on the layout, never in the dealer's hand. The dealer exchanges it for roulette chips, which carry no denomination printed on them. Each player at a table receives a distinct chip color so the dealer can tell whose bets are whose. You state the value you want each chip to represent, and the dealer places a marker on the rim showing that value. These chips are only good at that table; you must exchange them for regular casino chips before you leave.
Once you have chips, you place them on the layout before the dealer calls an end to betting. On a busy table you may be placing bets alongside several other players, so keep your chips in front of you and place them deliberately. After the ball drops, the dealer places a marker on the winning number, clears all losing bets first, and then pays winning bets. Do not reach onto the layout to collect or adjust chips after the result is called. The dealer handles all payouts; touching chips at the wrong moment is the fastest way to slow the table and irritate everyone on it.
When you are finished, tell the dealer you are done. The dealer exchanges your colored roulette chips for standard casino chips, which you can then take to the cashier. Roulette chips never leave the table.
The bet types on a 38-slot wheel
Every roulette bet falls into one of two families: inside bets and outside bets. Inside bets are placed on the numbered grid and cover specific numbers or small groups of them. They pay more but win less often. Outside bets sit around the perimeter of the layout and cover broad categories: red or black, odd or even, high or low, columns, and dozens. They pay less but win more frequently.
The table below compares the main bets on an American wheel. The payouts are fixed by the game's rules; the probability of winning follows from the 38-slot geometry. The house edge is the same on nearly every bet on this wheel, which is unusual among casino games and worth understanding.
| Bet | Covers | Payout | Win probability | House edge |
|---|---|---|---|---|
| Straight up | One number | 35 to 1 | 1 in 38 | Same as all other bets below |
| Split | Two adjacent numbers | 17 to 1 | 2 in 38 | Same as all other bets below |
| Street | Three numbers in a row | 11 to 1 | 3 in 38 | Same as all other bets below |
| Corner | Four numbers in a square | 8 to 1 | 4 in 38 | Same as all other bets below |
| Six line | Six numbers in two rows | 5 to 1 | 6 in 38 | Same as all other bets below |
| Red/black, odd/even, high/low | 18 numbers | 1 to 1 | 18 in 38 | Same as all other bets below |
| Dozens, columns | 12 numbers | 2 to 1 | 12 in 38 | Same as all other bets below |
The reason the edge is uniform is the double zero. On a 37-slot European wheel, a straight-up bet pays 35 to 1 against 1-in-37 odds, and the gap between those two numbers is the house edge. On a 38-slot American wheel, the same 35-to-1 payout is offered against 1-in-38 odds. The extra pocket widens the gap. The same arithmetic applies to every bet that pays true odds for a 36-number wheel, which is nearly all of them. The one exception on some American layouts is a five-number bet covering 0, 00, 1, 2, and 3, which carries a larger edge than the rest of the table and is best avoided.
None of this means you should expect to lose on any particular spin. It means the average loss per unit wagered is higher on the 38-slot wheel than on the 37-slot wheel, and it stays higher no matter how you combine bets. Betting red and black at the same time does not cancel the edge; it just spreads it across two bets that both lose when a zero appears.
What the double zero changes
The practical effect of the extra pocket shows up most clearly on the even-money bets. On a 37-slot wheel, red covers 18 of 37 pockets. On a 38-slot wheel, red still covers 18 pockets, but now there are 20 ways to lose: 18 black numbers plus the two green zeros. The same is true for black, odd, even, high, and low. The zeros are not neutral outcomes; they are losing outcomes for every even-money bet unless you have placed a separate zero bet.
If you have a choice of wheels, the 37-slot single-zero layout is the better arithmetic on every bet. If the only wheel available has 38 slots, the game is still playable, but you should size your bets knowing that the expected loss per spin is higher than it would be across the room on a single-zero wheel. That difference is not a matter of opinion or strategy. It is built into the wheel before the ball is released.
Procedural mistakes new players make
The first mistake is buying in with a chip value that does not match how you intend to bet. If you plan to make mostly outside bets at the table minimum, a stack of high-value chips forces you to bet more than you intended on every spin. State a chip value that lets you make your preferred bets in multiples you are comfortable with. The dealer will accommodate any reasonable denomination.
The second mistake is placing late bets. Once the dealer calls no more bets, the layout is closed. A hand reaching in after that call is at best a breach of table procedure and at worst a reason for the pit boss to review your action. Watch the dealer, place your bets before the call, and keep your hands back once the ball begins to slow.
The third mistake is treating the displayed history board as information. Many American roulette tables show the last twenty or so winning numbers. The board is a record of what happened, not a predictor of what happens next. Each spin is independent. The wheel does not owe you a number, and a streak of reds does not make black more likely. Chasing the board is a fast way to make bets you would not otherwise have made.
FAQ
Why does the American wheel have worse odds than the European wheel?
The American wheel has 38 slots because it adds a double zero alongside the single zero. The payouts are the same as on a 37-slot wheel, but the extra pocket means every bet wins slightly less often. That gap widens the house edge on every bet except the five-number bet, which is worse still.
Is there a roulette strategy that works better on a 38-slot wheel?
No betting system changes the underlying probabilities. Progression systems that raise or lower your stake after wins or losses rearrange when you win and lose, but the edge remains on every spin. The only decisions that change your expected loss are which wheel you choose and how much you wager per spin.
Can I bet on the zeros to cover my even-money bets?
You can place a separate bet on the zero or double zero, but it does not turn your even-money bet into a break-even proposition. The zero bet pays at its own odds and loses on the other 36 or 37 numbers. Combining bets changes the distribution of outcomes, not the house edge on each individual wager.
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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.