The wheel carries 37 or 38 pockets, and that single fact changes the odds
Walk up to a roulette table and the first thing you will see is a wheel with numbered pockets and a betting layout printed on the felt. The wheel is not just decoration. The number of pockets on it, and whether one of them is a single zero or a double zero, determines the house edge on every bet you place. Two wheel types dominate: the European layout with 37 pockets, and the American layout with 38.
The numbered pockets run from 0 to 36. On a European wheel there is one zero pocket, coloured green. On an American wheel there are two green pockets, a single zero and a double zero. The remaining 36 pockets are split evenly between red and black, with the numbers arranged in a sequence that looks random but is deliberately designed to alternate colours and spread high and low numbers around the wheel.
The sequence matters less than the count. Every bet on a European wheel is settled against 37 possible outcomes. Every bet on an American wheel is settled against 38. The extra pocket on the American layout increases the house edge because it adds a losing outcome to bets that would otherwise pay as if there were 36 numbers. That is the core mechanic to understand before you sit down.
How the numbered pockets drive payouts
Roulette payouts are built around the number of pockets a bet covers. A straight-up bet on a single number pays 35 to 1. The mathematics behind that payout assumes a wheel with 36 numbered pockets and no zero. The zero pocket is what gives the house its edge: the payout stays at 35 to 1 even though the wheel now has 37 or 38 pockets, so the true odds of hitting a single number are slightly worse than the payout suggests.
This principle scales across every bet type. A split bet covering two numbers pays 17 to 1. A street bet covering three numbers pays 11 to 1. A corner bet covering four numbers pays 8 to 1. A six-line bet covering six numbers pays 5 to 1. The outside bets work the same way: red or black, odd or even, and high or low each pay 1 to 1, but the green zero pocket means those bets are not a true 50-50 proposition.
RTP and house edge are complements: they sum to 100% for the same game. On a European wheel, the single zero creates a house edge that is lower than on an American wheel, where the double zero adds another losing pocket to every bet. The exact percentages are published in the game's information panel or the operator's rules page, and they differ by wheel type. What you need to know at the table is simpler: the American layout is the more expensive version of the same game because it has one extra pocket that works against you.
The sequence of a round, from buy-in to settlement
A round of roulette moves faster than most new players expect. The dealer controls the pace, and the sequence repeats without pause between spins. Knowing the flow before you sit down prevents the most common procedural mistakes.
You begin by buying in. Place your cash on the felt, never directly into the dealer's hand. The dealer exchanges it for roulette chips, which are different from the chips used at other table games. Roulette chips have no denomination printed on them; each player at the table gets a distinct colour so the dealer can tell whose bets are whose. The value of each chip is set when you buy in and displayed on the table.
Once the dealer clears the previous spin's result, the betting window opens. You place chips on the layout to mark your bets. Inside bets go on individual numbers or small groups of numbers. Outside bets go on the boxes around the edge of the layout: red, black, odd, even, high, low, dozens, and columns. You may place multiple bets on the same spin, and they are settled independently.
The dealer announces that no more bets are allowed, then spins the wheel and releases the ball in the opposite direction. When the ball drops into a pocket, the dealer marks the winning number on the layout, clears all losing bets, and pays winners from the outside in. Your winning chips stay on the layout until the dealer has paid them; you collect them after the payout is complete. The next betting window opens immediately.
Inside bets and outside bets compared
Every roulette bet falls into one of two categories, and the distinction is about coverage versus payout size. Inside bets cover fewer numbers and pay more when they hit. Outside bets cover many numbers and pay less, but they win more often. Neither category changes the house edge on its own; the edge is set by the wheel type, not by which bet you choose.
| Bet type | Numbers covered | Payout | What it means at the table |
|---|---|---|---|
| Straight-up | 1 | 35 to 1 | A chip placed fully inside a single number's box |
| Split | 2 | 17 to 1 | A chip on the line between two adjacent numbers |
| Street | 3 | 11 to 1 | A chip on the outer edge of a row of three numbers |
| Corner | 4 | 8 to 1 | A chip on the intersection of four numbers |
| Six-line | 6 | 5 to 1 | A chip on the outer edge where two rows meet |
| Red or black | 18 | 1 to 1 | An outside bet on the colour of the winning number |
| Odd or even | 18 | 1 to 1 | An outside bet on the parity of the winning number |
| High or low | 18 | 1 to 1 | An outside bet on 1-18 or 19-36 |
| Dozens | 12 | 2 to 1 | An outside bet on 1-12, 13-24, or 25-36 |
| Columns | 12 | 2 to 1 | An outside bet on one of the three vertical columns |
The zero pocket is a losing outcome for all of these bets unless you have placed a specific bet on zero itself. On an American wheel, the double zero is a separate pocket and a separate losing outcome. Some tables offer a five-number bet covering 0, 00, 1, 2, and 3, but it carries a higher house edge than any other bet on the layout because it pays 6 to 1 while covering five numbers on a 38-pocket wheel.
Why the wheel type changes every decision you make
If you have a choice between tables, the wheel type is the single most important piece of information to check before you buy in. A European wheel with 37 pockets and a single zero gives the house a smaller edge on every bet than an American wheel with 38 pockets and a double zero. The difference is not a matter of strategy or skill; it is built into the equipment.
The extra pocket does not change how the game is played or how payouts are calculated. It changes how often you expect to lose. Over a large number of spins, the American layout returns a smaller percentage of total wagered money to players than the European layout. That is a long-run statistical average, not a per-session guarantee, but it is the correct way to compare the two games.
Some operators offer French roulette, which uses the European wheel but adds rules that affect even-money bets when the ball lands on zero. The most common of these rules returns half the stake or holds the bet for the next spin. These rules change the expected loss on even-money bets specifically, and they are printed in the table rules. If a table offers them, the information panel or the dealer will state the exact terms.
Procedural mistakes that cost new players time and money
The first mistake is buying in with chips from another table. Roulette chips are colour-coded per player and have no cash value away from the table where they were issued. If you carry them to another table or to the cashier, they cannot be redeemed. Cash them out at the roulette table before you leave.
The second mistake is placing a bet after the dealer has announced that no more bets are allowed. Once the ball is in motion, the betting window is closed. A late bet will be returned to you, and repeated late bets will draw the dealer's attention. Watch the dealer, not the wheel, and place your bets during the open window.
The third mistake is misunderstanding what the zero pocket does to outside bets. Red, black, odd, even, high, and low are not 50-50 bets. The green zero pocket is a losing outcome for all of them. On an American wheel, both zero pockets are losing outcomes. That is why the payout is 1 to 1 but the true odds are worse than even.
FAQ
Are the numbers on a roulette wheel in the same order on every wheel?
The sequence of numbers is standard for each wheel type, but the arrangement is not the numbers in counting order. The European sequence and the American sequence are different from each other, and both are designed to alternate red and black pockets while scattering high and low numbers around the wheel. The exact sequence is printed in most roulette rule guides and does not affect the odds.
Does the zero pocket pay anything if I bet on red or black?
No. The zero pocket is a losing outcome for red, black, odd, even, high, and low bets unless the table rules include a special provision for even-money bets when zero lands. Some European tables offer a rule that returns part of the stake or holds the bet for the next spin, but the standard settlement is a loss on the zero.
How do I know which wheel type a table is using?
Look at the wheel itself. A European wheel has one green zero pocket. An American wheel has two green pockets, labelled 0 and 00. The betting layout will also show the difference: an American layout includes a 00 box on the felt. If you are unsure, ask the dealer before you buy in.
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