The Wheel You Sit Down To Changes the Maths
Before you buy in, look at the wheel itself. If it has a single green pocket marked zero, you are looking at a European-style layout with 37 divisions. If it also has a second green pocket marked double zero, the wheel has 38 divisions. That one extra pocket is not a cosmetic difference. It changes the house edge on nearly every bet on the table, which is why the first thing a player should do at any roulette table is identify which wheel is in front of them.
A roulette wheel is a shallow, spun bowl with numbered pockets around its rim. Each pocket is a division. The ball lands in exactly one division per spin, and the number printed in that pocket is the winning number. The divisions are not arranged in numerical order; they are arranged to alternate red and black, high and low, odd and even as evenly as the physical layout allows, with the zero pockets in green.
What the Divisions Are
Every roulette wheel divides its circumference into a fixed set of pockets. The numbers run from 0 to 36. On a European wheel, those 37 numbers are the entire wheel: 0, then 1 through 36. On an American wheel, the same 0 through 36 appears, plus a second zero pocket labelled 00, giving 38 divisions in total.
The zero pockets are the house's structural advantage. When the ball lands in a zero pocket, the even-money outside bets—red or black, odd or even, high or low—do not pay out. Depending on the table rule, those bets may lose outright or be held for the next spin. The zero pockets are also losing numbers for most inside bets. The extra 00 pocket on an American wheel means the ball has one more way to land on a number that does not help the player.
| Feature | European Wheel | American Wheel |
|---|---|---|
| Total divisions | 37 | 38 |
| Zero pockets | 1 (single zero) | 2 (single zero and double zero) |
| Numbered pockets | 0 to 36 | 0, 00, 1 to 36 |
| Effect on even-money bets | Zero pocket is the main losing number | Two zero pockets are losing numbers |
| House edge on most bets | Lower | Higher |
Some venues in Europe and elsewhere also use a French layout, which is the same 37-division wheel as the European one but with different table rules for the outside bets. The wheel itself is identical; the difference is in what happens when the zero appears. Do not confuse the wheel with the table. The divisions are on the wheel; the betting layout is printed on the felt.
From Buy-In to Settlement: How a Round Moves
You sit down, place cash or chips on the table, and the dealer exchanges it for roulette chips. Roulette chips are often colour-coded per player so the dealer can tell whose bets are whose. The dealer will not hand you the chips directly in most venues; you place your cash on the felt and the dealer slides the chips to you.
Once you have chips, you place them on the layout. The layout is a printed grid showing every number on the wheel, plus zones for outside bets. You can place bets until the dealer announces that no more bets are allowed. The dealer then spins the wheel in one direction and sends the ball travelling in the other. When the ball drops into a division, the dealer marks the winning number, clears the losing bets, and pays the winners according to the posted odds.
You do not need to do anything during the spin. Your decisions all happen before the ball is released: which bets to place, how much to stake on each, and when to stop. After settlement, the next round begins and you may bet again, change your bets, or colour up and leave.
Bet Types and Why Their Edges Differ
Roulette bets fall into two broad groups: inside bets on specific numbers or small groups of numbers, and outside bets on larger categories. The payout for each bet is set so that the house keeps an edge. On a European wheel, every bet on the layout carries the same house edge because the payout is calculated as if there were 36 paying divisions, but the wheel has 37. The extra zero pocket is the gap. On an American wheel, the same logic applies with 38 divisions, which widens the gap.
The payout odds do not change between the two wheels. A straight-up bet on a single number pays 35 to 1 on both. But the chance of winning is lower on the American wheel because there is one more pocket that is not your number. That is why the house edge is higher there even though the payout looks identical.
| Bet | Covers | Payout | Why the Edge Exists |
|---|---|---|---|
| Straight up | One number | 35 to 1 | Payout assumes 36 divisions; wheel has 37 or 38 |
| Split | Two adjacent numbers | 17 to 1 | Same gap between payout odds and true odds |
| Street | Three numbers in a row | 11 to 1 | Payout below the true 1-in-12.33 or 1-in-12.67 chance |
| Red or black | 18 numbers | 1 to 1 | Zero pockets are neither red nor black |
| Odd or even | 18 numbers | 1 to 1 | Zero pockets are not odd or even for this purpose |
The key point is that on a European wheel, the zero pocket is the single structural gap. On an American wheel, the zero and double zero both sit outside the even-money categories and outside most inside bets. The wheel does not change the payout; it changes the probability.
What Strategy Charts Can and Cannot Do
Roulette does not have a basic-strategy chart in the way blackjack does, because there is no decision that changes the composition of the wheel. In blackjack, the player's choices—hit, stand, double, split—interact with the specific rule set in use, which is why published basic-strategy charts derive from the exact deck count, dealer stand rules, and doubling and splitting rules at that table. In roulette, the only decision is which bets to place, and every bet on a given wheel carries the same house edge, with a small number of exceptions under specific rule variants.
The closest thing to a strategic choice in roulette is wheel selection. A European wheel has a lower house edge than an American wheel on the same bets. If you have a choice of tables, the wheel with fewer divisions is the better structural choice, not because it makes you likely to win, but because it reduces the expected rate of loss on every spin. That is a mathematical fact about the layout, not a prediction about the next spin.
Some tables offer a rule called la partage or en prison on even-money bets. Under la partage, a losing even-money bet on zero returns half the stake. Under en prison, the losing bet is held for the next spin. These rules reduce the house edge on those specific even-money bets, but they do not change the wheel. They change the settlement rule after the ball has already landed.
Mistakes That Cost New Players Before the Ball Spins
The first mistake is not checking which wheel is in front of you. A player who sits at an American wheel without noticing the double zero is accepting a higher house edge on every bet, and the difference is entirely avoidable if another table is available.
The second mistake is confusing payout odds with true odds. A straight-up bet pays 35 to 1, which sounds generous. But on a European wheel the true chance is 1 in 37, and on an American wheel it is 1 in 38. The payout is fixed at 35 to 1 on both. The gap between 35 to 1 and the true odds is exactly where the house edge lives. No betting pattern removes that gap.
The third mistake is placing late bets. Once the dealer calls no more bets, any chip that lands on the layout after the call is void or returned, and repeated late betting can get a player removed from the table. The same applies to touching chips after the ball has dropped. Watch the dealer's hand signal and the moment the ball begins to slow, and have your bets placed before that point.
Reading the Table Before You Buy In
Every roulette table carries the information you need. The wheel itself shows the divisions. The felt layout shows the minimum and maximum bet for the table. The posted rules or the dealer can tell you whether the table uses la partage, en prison, or neither. If you are playing online, the game information panel or help screen states the wheel type and the table rules.
The number of divisions is the first fact to establish because it is the one that most changes the mathematics of the session. Everything else—the payout odds, the bet types, the sequence of play—is the same on both wheels. The divisions are the variable.
FAQ
Why does the American wheel have an extra division?
The American layout adds a double zero pocket to the standard 0 through 36 set. The extra pocket increases the house edge on most bets because the payout odds stay the same while the chance of winning drops. The double zero is a structural feature of the American wheel, not a rule that can be opted out of at that table.
Do the zero pockets count as red or black?
No. The zero and double zero pockets are green. They are not red, not black, not odd, and not even for the purposes of the outside bets. When the ball lands in a zero pocket, the even-money outside bets lose or are subject to the table's zero rule, depending on the variant in use.
Can I choose a wheel with fewer divisions online?
Yes, if the operator offers both. The game lobby or information panel states which wheel type each roulette title uses. European and French titles use the 37-division wheel; American titles use the 38-division wheel. Choose the wheel, not just the table felt, because the felt looks similar across both layouts.
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