The number that changes every bet you place
When you walk up to a roulette table, the wheel is the first thing you see, but the count of its pockets is the last thing most players think about. That count is not decoration. It is the denominator in every probability on the layout, and on an American wheel it is 38: the numbers 1 through 36, plus a single zero and a double zero. Those two green pockets are not a cosmetic difference from other wheels. They are the reason the same bet pays the same odds while losing more often than it would on a wheel with only one zero.
A standard American roulette wheel carries 38 pockets in total. The numbered pockets alternate red and black around the wheel, while the 0 and 00 pockets sit in green. The layout printed on the felt mirrors those 38 outcomes, and every bet you can place is settled against one of them. If you are reading a rule sheet or a game information panel, the wheel description will state the pocket count outright, because it is the single most important structural fact about the game.
American and European wheels compared
The American wheel is not the only roulette format in circulation. Many venues also run a European wheel, and the difference between the two is exactly one pocket. That single pocket changes the expected rate of loss on every wager, even though the payouts printed on the layout stay the same.
| Feature | American wheel | European wheel |
|---|---|---|
| Total pockets | 38 | 37 |
| Zero pockets | 0 and 00 | 0 only |
| Number range | 1-36 | 1-36 |
| Payout for a straight-up win | Fixed odds printed on the layout | Fixed odds printed on the layout |
| Effect on house edge | Higher on equivalent bets | Lower on equivalent bets |
The payouts do not change between the two formats. A straight-up bet on a single number pays the same fixed multiple of the stake on both wheels. What changes is how often that bet wins, because the American wheel has one additional pocket that pays no standard bet. That is the entire mechanism: same reward, one more way to lose.
How the extra pocket works against you
House edge and return to player are complements. They sum to 100% for the same bet under the same rule set, so when the edge rises, the long-run return falls by the same amount. On an American wheel, the double zero is the pocket that pushes the edge up. It is not a special symbol that triggers a side game or a bonus; it is simply a losing outcome for nearly every wager on the felt.
As an example, suppose a wheel has 38 equally likely pockets and you bet on one of them. Your chance of hitting that pocket on any spin is 1 in 38. If the bet paid at true odds for a 38-pocket wheel, a winning spin would return your stake plus 37 times it. The casino instead pays a lower fixed multiple, and the gap between that payout and the true odds is the house edge. The same arithmetic on a 37-pocket wheel leaves a smaller gap, because there is one fewer losing pocket in the denominator.
This is not a small detail for a player deciding which table to join. Two wheels can look nearly identical, but the one with the double zero charges a higher expected price for every chip you put down. The wheel's pocket count, not the colour of the felt or the minimum stake, is the first thing to check.
The sequence of a round
A round of roulette moves through a fixed sequence, and knowing it keeps you from fumbling chips at the wrong moment.
You buy in at the table, and the dealer exchanges your cash for roulette chips. These chips are usually distinct from the chips used at other table games, and at some tables each player receives a unique colour so the dealer can tell stacks apart. The dealer announces when betting opens. You place chips on the layout, either on a single number, a group of numbers, a colour, or one of the other marked areas. The dealer then spins the wheel in one direction and sends the ball travelling in the other. From the moment the ball is released, the table rules determine when betting closes, and any chip placed after that point is void or returned.
When the ball settles into a pocket, the dealer marks the winning number on the layout, clears all losing bets, and pays winning bets according to the fixed odds printed on the felt. Only after the winning bets are paid does the next round open. A common new-player mistake is reaching toward the layout while the dealer is still clearing or paying, which can create a dispute about which chips belong to whom. Keep your hands back until the dealer signals the next betting window.
Main bet types and how their edges differ
Not every bet on an American roulette layout loses at the same rate. The payouts are fixed, but the probability behind each wager differs, so the house edge differs from one bet type to the next. The table below compares the standard bet categories on an American wheel.
| Bet type | What it covers | Payout structure | Edge relative to other bets |
|---|---|---|---|
| Straight-up | One single number | Fixed multiple of the stake | Highest edge among standard inside bets |
| Split | Two adjacent numbers | Lower fixed multiple than straight-up | Same edge class as straight-up |
| Street | Three numbers in a row | Lower fixed multiple than split | Same edge class as straight-up |
| Corner | Four numbers meeting at a corner | Lower fixed multiple than street | Same edge class as straight-up |
| Red/black, odd/even, high/low | 18 numbers each | Even-money payout | Lower edge than inside bets |
| Five-number basket | 0, 00, 1, 2, 3 | Fixed multiple of the stake | Highest edge on the American layout |
The five-number basket is specific to the American wheel and is the worst standard bet on the layout, because it covers only five pockets while paying as if the arithmetic were more generous. Even-money bets carry a lower edge than inside bets, but on an American wheel they still lose more often than the same bets on a European wheel, because the 0 and 00 both sit outside the red, black, odd, even, high and low groupings.
None of these differences turns any bet into a winning play. A lower-edge bet loses more slowly in expectation; it does not reverse the direction of the edge. The choice is about the rate of expected loss, not about finding a bet the house has overlooked.
Where the numbers on your table are printed
You do not need to memorise every payout. The table layout prints the odds for each betting area, and the wheel itself shows the pocket sequence. What the layout does not always spell out is the house edge, because the edge is a property of the wheel's pocket count interacting with those printed payouts. The game information panel, the operator's rules page, or the help screen on an electronic table will usually state the wheel type, and that is the figure that tells you which arithmetic applies.
When a table is labelled simply as roulette without specifying the wheel type, look at the wheel. If you see both a 0 and a 00, you are on a 38-pocket American wheel. If you see only a single 0, you are on a 37-pocket European wheel. Some venues run both formats on the same floor, sometimes at different minimums, and the cheaper table is not necessarily the better deal if it carries the extra zero.
Procedural mistakes that cost new players
The first mistake is playing the five-number basket without realising it exists only on the American layout and carries the highest edge among standard bets. It looks like a convenient way to cover the zeros plus a small block of numbers, but the payout is set below what the five-pocket coverage would justify.
The second mistake is confusing the wheel's pocket count with the number of betting spots on the felt. The layout shows the same 38 outcomes, but some betting areas cover overlapping groups, and a player can accidentally stack chips in a way that creates a bet they did not intend. Before the ball is released, read your chips back to yourself by outcome: which pockets win for you, and which lose.
The third mistake is assuming that a roulette strategy chart works the same on every wheel. Roulette does not have a strategy chart in the sense that blackjack does, because no decision you make after the spin changes the probabilities. The only structural choice is which wheel to play and which bets to place, and that choice depends entirely on the pocket count in front of you.
FAQ
Why does the American wheel have two zeros?
The double zero is a design feature of the American format that adds one more losing pocket for standard bets. It is not a separate game or a bonus trigger. Its only structural effect is to raise the house edge on every bet compared with a single-zero wheel.
Do all American roulette tables use the same 38-pocket wheel?
A standard American roulette wheel has 38 pockets, and a table described as American roulette should use that format. Some venues also offer European wheels with 37 pockets, so the wheel type should be confirmed at the table or in the game rules before you bet.
Does the extra zero change the payout on a winning number?
No. The payout for a straight-up win is the same fixed multiple of the stake on both American and European wheels. The difference is that the American bet wins less often, because there are 38 equally likely pockets instead of 37, and the payout has not been increased to match.
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