The 38-pocket wheel is the American layout, and the extra pocket is not decoration
A roulette wheel with 38 numbers is the American configuration. It carries the numbers 1 through 36, a single zero, and a double zero. The European layout stops at 37 pockets because it has no double zero. That one additional pocket is the entire reason the two wheels play differently, and it is the first thing to check when you sit down, because it changes the arithmetic on every wager you can place.
The numbers are not arranged in numerical order around the wheel. They are distributed in a fixed sequence designed to alternate high and low, odd and even, and red and black as evenly as the wheel geometry allows. The zero and double zero sit opposite each other on most American wheels, both in green pockets. The sequence is standardised enough that experienced players can recognise a wheel at a glance, but the sequence itself does not affect the odds. What matters is the count: 38 pockets, each equally likely on a fair spin.
What you are betting on
Every roulette wager is a bet on which pocket the ball lands in, expressed through categories. You are not betting against other players. You are betting against the wheel, with the house holding the mathematical advantage built into the payout schedule.
A straight-up bet names a single number and pays 35 to 1. If the wheel has 38 pockets, a straight-up bet on one number has 1 winning pocket and 37 losing pockets. The payout of 35 to 1 is short of the true odds of 37 to 1. That shortfall is the house edge. The same logic applies to every other bet on the layout: the payout is set as if the wheel had 36 numbers, but the American wheel has 38. The two extra green pockets, not one, are where the operator's advantage lives.
The main bet types and how their edges differ
Roulette bets fall into two broad families: inside bets, which sit on the numbered grid, and outside bets, which sit around its edges. Inside bets cover fewer numbers and pay more; outside bets cover more numbers and pay less. The house edge on the American wheel is the same for nearly all of them, because nearly all of them are paid as if the zeroes did not exist. The exception is the five-number bet, which is worse.
| Bet | Pockets covered | Payout | What the 38-pocket wheel does to it |
|---|---|---|---|
| Straight-up | 1 | 35 to 1 | Paid as if the wheel had 36 pockets; the two zeroes create the shortfall |
| Split | 2 | 17 to 1 | Same structural shortfall as straight-up |
| Street (three numbers) | 3 | 11 to 1 | Same structural shortfall |
| Corner (four numbers) | 4 | 8 to 1 | Same structural shortfall |
| Five-number (0, 00, 1, 2, 3) | 5 | 6 to 1 | Worse than the others; the only bet on the American layout with a materially higher edge |
| Six-line | 6 | 5 to 1 | Same structural shortfall as straight-up |
| Column or dozen | 12 | 2 to 1 | Same structural shortfall |
| Red/black, odd/even, high/low | 18 | 1 to 1 | Loses on both zeroes, which is what gives the house its edge |
The five-number bet deserves a warning because it is the one wager on the American layout that is structurally different from the rest. It covers 0, 00, 1, 2 and 3, and it pays 6 to 1. If the payout were set consistently with the other inside bets, five covered numbers would pay closer to 6.2 to 1. The rounding down to 6 to 1 makes it the worst bet on the table. There is no strategic reason to place it.
Outside bets look safer because they cover 18 numbers at a time, but on the American wheel the two green pockets are not covered by red, black, odd, even, high or low. When the ball lands in either zero, every even-money outside bet loses. That is the mechanism by which the house edge is collected on those bets. The edge is not hidden; it is sitting in plain sight in the two green pockets.
How a round plays from buy-in to settlement
You buy in at the table with cash, and the dealer converts it into roulette chips. These chips are usually a distinct colour assigned to you alone, so the dealer can tell whose bets are whose. They have no value away from the table; when you leave, you exchange them back for standard casino chips or cash at the table.
A round moves through a fixed sequence. The dealer opens betting. Players place chips on the layout, and may keep placing them until the dealer calls no more bets. The dealer spins the wheel in one direction and launches the ball in the other. When the ball drops into a pocket, the dealer places a marker on the winning number, clears losing bets, and pays winners. Only then may you place chips for the next spin.
Each decision point in that sequence is simple, but the discipline is in respecting it. Once the dealer has called no more bets, your hands stay off the layout. Once the marker is down, you do not touch your chips until the dealer has finished paying and clearing. The table staff run the sequence, and the sequence is what keeps a busy table legible.
What strategy charts can and cannot do
Roulette is not a game where a strategy chart changes the house edge the way basic strategy does in blackjack. In blackjack, published basic-strategy charts derive from the specific rule set in use: deck count, dealer stand rules, doubling and splitting rules. Change the rules, and the chart changes. Roulette has no equivalent decision tree, because no decision you make after the spin changes what the wheel does.
What you control at a roulette table is narrower: which bets you place, how much you wager on each, how many spins you play, and when you stop. Bet selection changes the edge only in one meaningful way on the American wheel: avoiding the five-number bet, and preferring the 37-pocket European layout when it is available, because the missing double zero changes the arithmetic on every bet. Nothing else you do alters the built-in edge. A betting progression, however it is arranged, redistributes outcomes across a session; it does not remove the shortfall built into the payout schedule.
Procedural mistakes that cost new players
The first mistake is buying in and then not noticing which wheel is in front of you. A 38-pocket wheel and a 37-pocket wheel look similar at a glance, and the difference is one green pocket. If you have a choice of tables, the wheel with fewer pockets is the better arithmetic on every bet you can place. Check before you put chips down.
The second mistake is placing the five-number bet because it sits at the top of the layout and looks like it covers a useful slice of the wheel. It is the only bet on the American layout with a materially worse edge than the rest of the table, and it is easy to place by accident when reaching for the 0, 00, 1, 2 and 3 area.
The third mistake is treating even-money outside bets as coin flips. They are not, on the American wheel. The two green pockets mean an even-money bet covers 18 of 38 pockets, not 18 of 36. The gap between those two fractions is the house edge, and it is collected every time the ball lands in a zero. Understanding that gap before the first spin is the difference between knowing what you are playing and only knowing what you are hoping for.
FAQ
Is a 38-number roulette wheel the same as an American wheel?
Yes. The American layout is defined by the presence of both a single zero and a double zero, giving 38 pockets: 1 through 36 plus the two green zeroes. A wheel with 37 pockets has one zero and is the European configuration.
Does the five-number bet ever make sense?
No. It is the only bet on the American layout with a materially higher house edge than the rest of the table, because its payout is rounded down relative to the number of pockets it covers. If you want to cover the zero section, a split or a straight-up bet carries the standard edge instead of the worse one.
Why do even-money bets lose on zero?
Because zero and double zero are green, and the even-money wagers cover red, black, odd, even, high and low, none of which include the green pockets. On a 38-pocket wheel, an even-money bet covers 18 winning pockets and 20 losing ones, which is where the house edge on those bets comes from.
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