Why the extra pocket matters before you buy in
You sit down, put cash on the felt, and get colored chips. The wheel in front of you has 38 pockets, not 37. That one extra pocket is the whole reason the math on this table is different from the European layout, and it changes nothing about how the ball spins but everything about how fast your bankroll drains on average.
A roulette wheel has 38 colored slots when it is the American layout: the numbers 1 through 36, a single zero, and a double zero. The numbers alternate red and black. The zero and double zero are green. That is the full inventory of the wheel. The ball lands in exactly one pocket, every spin, with no memory of the spin before it.
The practical consequence: on a 37-pocket European wheel, the single zero is the only pocket that belongs to neither red nor black, neither odd nor even, neither high nor low. On a 38-pocket wheel, the double zero adds a second such pocket. Your even-money bets still pay 1 to 1, but they now lose on two green pockets instead of one. That is the entire difference in a sentence.
What the 38 pockets mean for the house edge
House edge and RTP are complements: they sum to 100% for the same game. On the American layout, an even-money bet such as red covers 18 of the 38 pockets. The bet pays 1 to 1, but the true odds against winning are 20 to 18. The gap between the payout and the true odds is the house edge, and it is wider on this wheel than on the single-zero layout because the extra green pocket sits outside every outside bet.
This does not mean the wheel is rigged or that the casino adjusts outcomes. It means the payout schedule pays slightly less than the pocket count would justify if the game were fair at even money. Every bet on the table carries the same structural relationship: the payouts are fixed, the wheel has 38 pockets, and the two green pockets are excluded from the red/black, odd/even, and high/low splits.
The table below shows how the main bet categories compare on the same 38-slot wheel.
| Bet type | Pockets covered | Payout | Why the edge differs |
|---|---|---|---|
| Straight up (one number) | 1 | 35 to 1 | True odds are 37 to 1; the payout is short by two units because of both green pockets. |
| Split (two numbers) | 2 | 17 to 1 | Same shortfall, scaled to two covered pockets. |
| Street (three numbers) | 3 | 11 to 1 | Payout reflects the same 38-pocket denominator. |
| Red or black | 18 | 1 to 1 | Loses on 0 and 00; 20 losing pockets against 18 winning ones. |
| Odd or even | 18 | 1 to 1 | Same as red/black; the two green pockets are neither odd nor even. |
| High or low (1-18 / 19-36) | 18 | 1 to 1 | Same structure; the green pockets fall outside both ranges. |
If you want a single number to carry away from this section, carry the pocket count: 38. Every payout on the layout is built around that denominator, and the two green pockets are the reason the payouts are short.
How a round goes, from buy-in to settlement
The sequence is the same on every wheel, but the 38-slot layout adds one decision point at the start: you are choosing to play the double-zero game. Nothing else about the ritual changes.
You place cash on the table, never into the dealer's hand. The dealer converts it into wheel chips, which are colored differently from the chips at other tables so the staff can tell whose stack is whose. These chips have no cash value away from the table; you exchange them back before you leave.
You then place bets by putting chips on the layout. The dealer announces when betting is closed, usually with a hand motion and the words "no more bets." The ball is already travelling. From that moment, you cannot touch your chips. When the ball drops, the dealer places a marker on the winning number, clears all losing bets first, and then pays winning bets. Your losing chips are gone. Your winning chips stay on the layout until you collect them or leave them up for the next spin.
At the end of your session, you push your wheel chips toward the dealer and ask to color up. The dealer counts them and gives you standard casino chips in return. Those you can take to the cashier.
The decision points and what they control
Roulette gives you fewer decisions than almost any other table game, and none of them change the house edge. What you control is which bets you place, how much you stake, and how long you stay.
Bet selection matters because the edge is constant across the layout on an American wheel, but the variance is not. A straight-up number pays 35 to 1 and loses almost every spin. An even-money bet pays 1 to 1 and wins just under half the time. Both carry the same house edge, but they produce very different sessions. A player betting single numbers will see long losing streaks punctuated by occasional large hits. A player betting red will see a slow grind with frequent small wins and frequent small losses.
Stake sizing is a method, not a strategy to beat the game. If you bring a fixed amount and divide it into equal units, you are deciding how many spins you can afford to lose. That is a session-management decision, not an edge decision. No staking pattern changes the 38-pocket denominator.
Stopping rules are the only decision that reliably changes your outcome on a given night, and they change it by limiting exposure, not by improving the odds. A player who leaves after a fixed number of spins or a fixed loss limit has simply stopped playing a negative-expectation game. A player who keeps playing because a number is "due" is acting on a false belief: the wheel has no memory, and the odds on the next spin are identical to the odds on the first.
Inside bets and outside bets on the same layout
The layout divides into two zones. Inside bets are placed on the numbered grid and cover specific numbers or small groups. Outside bets sit around the grid and cover large categories such as red, black, odd, even, high, low, dozens, and columns.
The distinction matters for table minimums. Many tables require the total of your inside bets to meet the minimum, or the total of your outside bets to meet it, but not a mix. The posted minimum is on the table sign, and the dealer will tell you if a bet does not qualify.
The table below separates the two zones so you can read the layout at a glance.
| Zone | Common bets | What you are betting on | Payout pattern |
|---|---|---|---|
| Inside | Straight, split, street, corner, six line | One number or a small cluster of adjacent numbers | High payouts, low hit frequency |
| Outside | Red/black, odd/even, high/low, dozen, column | Broad categories covering 12 or 18 pockets | Low payouts, high hit frequency |
On the American wheel, the outside bets that cover 18 pockets all exclude the zero and double zero. The dozens and columns cover 12 numbers each and also exclude both green pockets. The green pockets are only winnable through inside bets that specifically include them, such as a straight bet on 0 or 00, or a split that pairs them.
What a strategy chart does and does not do for roulette
Roulette is not blackjack. In blackjack, the player makes decisions after seeing cards, and published basic-strategy charts derive from the specific rule set in use: deck count, dealer stand rules, doubling and splitting rules. Those charts reduce the house edge because the player's choices genuinely change the expected outcome of a hand.
Roulette has no such decision tree. Once you choose a bet, the wheel does the rest. A roulette strategy chart is therefore a staking or money-management chart, not a playing strategy. It may tell you how to size bets after wins and losses, or how to spread across the layout. What it cannot do is change the fact that every bet on a 38-slot wheel pays as if the wheel had 36 losing pockets for an even-money bet, when it has 20.
If you see a chart that promises to overcome the double-zero layout, read it as a description of how bets are grouped, not as a method for changing the edge. The edge is built into the payout schedule, and the payout schedule is printed on the felt.
Procedural mistakes that cost new players more than the edge
The first mistake is touching chips after the dealer has called no more bets. The call is not a suggestion. A late bet or a chip moved after the call will be returned or corrected, and on a busy table it marks you as someone who does not know the rhythm of the game.
The second is buying in mid-spin. Wait for the ball to drop and the dealer to finish paying before you put cash on the table. A dealer cannot take your money while the ball is in motion, and trying to force the moment slows the whole table.
The third is confusing wheel chips with cash chips. Your colored chips only work at that table. If you walk to the cashier with them, you will be sent back. Color up at the table first, then leave.
The fourth is playing a system that doubles bets after losses. On a 38-slot wheel, a losing streak on an even-money bet is common, and the required bet size grows fast. The table maximum, printed on the sign, will eventually stop the progression. No progression removes the edge; it redistributes when losses land.
FAQ
Why does the American wheel have 38 slots instead of 37?
The American layout adds a double zero alongside the single zero. Both are green and both sit outside the red/black, odd/even, and high/low bets. The extra pocket widens the gap between the payout odds and the true odds on every bet.
Are the colors on a 38-slot wheel the same as on a 37-slot wheel?
The number sequence is arranged differently, but the color rule is the same: numbers alternate red and black, and the zero pockets are green. The double zero is green on the American layout.
Does the double zero change how I should bet?
It changes the cost of every bet, not the mechanics of any bet. The same bet types exist on both wheels. On the 38-slot wheel, each bet loses slightly more on average because the payout schedule is built around a wheel with one extra losing pocket for outside bets.
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