What the 38 slots change before you sit down
A roulette wheel with 38 slots is not a detail. It is a different game from the 37-slot wheel, and the difference shows up on the felt, in the payout arithmetic, and in how fast a session bleeds. The 38-slot layout is the American wheel: numbers 1 through 36, a single zero, and a double zero. The extra zero pocket is not cosmetic. It changes the odds on every bet on the table, even the ones that do not mention zero at all.
When a player asks about a 38-slot wheel, the useful thing to know is that the board they are looking at carries a built-in advantage for the house that is larger than the 37-slot alternative. The wheel itself tells them which game they are in. If the zeros sit opposite each other and the numbers alternate red and black around the rim, that is the American layout. If there is only one green zero, that is the European layout.
The wheel and the table are two views of the same bet
Every roulette table has two surfaces: the wheel and the betting layout. The wheel determines outcomes. The layout is where money goes. On a 38-slot wheel, the layout carries a double zero in addition to the single zero, and the arrangement of the numbers on the wheel differs from the 37-slot version. The sequence around the rim is designed so that high and low numbers, red and black, odd and even are interleaved, but the exact order is not something a player needs to memorise. What matters is that the wheel has 38 equally likely resting places for the ball, and every bet is priced against that total.
The croupier's routine follows the same shape on either wheel. Players place chips on the layout before the croupier calls for no more bets. The ball is launched against the direction of the spinning wheel, drops into a pocket, and the croupier marks the winning number. Losing bets are cleared first, then winning bets are paid. A player who wants to sit down should buy in at the table, not hand cash to the croupier mid-spin, and should know that chips bought at the table carry no denomination printed on them; their value is set by the buy-in and applies only at that table.
How the extra zero changes the arithmetic
A straight-up bet on a single number pays 35 to 1. On a 37-slot wheel there are 37 pockets, so a player betting one unit on every number would wager 37 units and receive 36 back when the winning number lands: the 35-unit payout plus the original unit. The missing unit is the house's edge. On a 38-slot wheel the same cover-the-board exercise costs 38 units and returns 36. The extra pocket is the entire difference, and it applies to every bet because every bet is settled against the same wheel.
This is the cleanest way to see what the double zero does. It does not change the payout schedule. A straight-up bet still pays 35 to 1, a split still pays 17 to 1, a corner still pays 8 to 1. What changes is the denominator: the number of slots the payout is measured against. The payout schedule looks generous because it ignores the zeros. The zeros are the house's share.
| Bet type | Numbers covered | Payout | What the 38-slot wheel changes |
|---|---|---|---|
| Straight up | 1 | 35 to 1 | Chance of hitting falls from 1 in 37 to 1 in 38 |
| Split | 2 | 17 to 1 | Chance falls from 2 in 37 to 2 in 38 |
| Street | 3 | 11 to 1 | Chance falls from 3 in 37 to 3 in 38 |
| Corner | 4 | 8 to 1 | Chance falls from 4 in 37 to 4 in 38 |
| Six line | 6 | 5 to 1 | Chance falls from 6 in 37 to 6 in 38 |
| Red or black | 18 | 1 to 1 | Zeros are green, so an 18-number bet loses on 20 of 38 spins |
| Odd or even | 18 | 1 to 1 | Same: zeros are neither odd nor even for this bet |
The table above shows the pattern. Every bet's chance of winning is the number of covered pockets divided by 38 on the American wheel, and divided by 37 on the European wheel. The payout does not change. Therefore the expected loss per unit wagered is higher on the 38-slot wheel for every bet on the layout.
The five-number bet is the table's worst standard wager
The American layout carries one bet that does not exist on the 37-slot wheel: the five-number bet, sometimes called the basket. It covers 0, 00, 1, 2 and 3, and it pays 6 to 1. A player covering five numbers on a 38-slot wheel wins five times in 38 spins and receives seven units each time: the six-unit payout plus the original unit. Over 38 spins at one unit each, the player wagers 38 and receives 35. The gap is wider than on any other standard bet on the table.
This is a useful fact for a new player because the five-number bet sits prominently on the layout where the zero row meets the first column, and it looks like a convenient way to cover the zeros. It is convenient for the house. Any other bet on the table carries a smaller expected loss per unit. A player who wants the lowest-edge option on an American wheel should look at the even-money bets, which lose only when a zero lands, rather than the basket, which loses on 33 of 38 spins.
What a strategy chart can and cannot do
Roulette is not a game where a strategy chart changes the underlying odds 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 one rule and the correct play can change. Roulette has no decision points after the bet is placed. The wheel spins, the ball lands, and the payout is fixed.
What a player can control in roulette is which bet they place, how much they stake, and when they stop. A chart of bet types and payouts is a reference, not a strategy. The only decision that changes the expected rate of loss is avoiding the bets with the worst arithmetic, and on a 38-slot wheel the worst standard bet is the five-number basket. No progression, no pattern, and no observation of previous spins changes the fact that every spin is independent and every bet is priced against 38 pockets.
Procedural mistakes that cost new players more than the house edge
The first mistake is buying in at the wrong moment. A player who hands cash to the croupier while the ball is spinning creates confusion about whether the cash is a bet or a buy-in. The correct move is to place cash on the table between spins, say the value of the chips wanted, and let the croupier convert it. The croupier will not take cash directly from a player's hand at most tables.
The second mistake is touching chips after the call of no more bets. Once the croupier closes betting, a chip that is moved is a dispute waiting to happen, and the table's ruling will not favour the player. The third is misunderstanding table chips. Roulette chips are colour-coded to each player and have no printed value; they are worthless at the cashier until converted back to cash chips at the table. A player who walks away with them has left value behind.
The fourth is assuming the zeros are covered by red or black. They are not. The zeros are green, and on an American wheel they sit at both ends of the number line. A player betting red has 18 winning pockets and 20 losing pockets. That is the whole game in one sentence.
Where the house edge number comes from
The house edge on a given bet is the percentage of each wager the operator keeps as a mathematical expectation over a very large number of spins. It is not a per-session guarantee, and it is not a prediction of what any single player will experience. A player can win on a high-edge bet and lose on a low-edge bet in any given session. The edge describes the long-run rate of loss, not the short-run outcome.
For the same bet under the same rule set, house edge and RTP sum to 100%. A game's RTP is the complement of the house edge: the theoretical percentage of total wagered money returned to players over a very large number of spins. On a 38-slot wheel, the RTP on a straight-up bet is lower than on a 37-slot wheel because the payout is identical but the denominator is larger. The player does not need to memorise the exact percentages. They need to know that the 38-slot wheel is the more expensive game, and that the difference is visible every time the ball lands in a green pocket.
FAQ
Is a 38-slot wheel the same as American roulette?
Yes. The 38-slot layout is the American wheel: numbers 1 through 36, a single zero, and a double zero. The 37-slot layout has only a single zero and is commonly called the European wheel. The two wheels also arrange the numbers in a different order around the rim.
Which bet should a new player avoid on a 38-slot wheel?
The five-number bet covering 0, 00, 1, 2 and 3 carries the worst standard payout arithmetic on the American layout. It pays 6 to 1 while covering five of 38 pockets. Every other standard bet on the table has a smaller expected loss per unit wagered.
Does watching previous spins help on a 38-slot wheel?
No. Each spin is independent, and the ball has no memory of where it landed before. A number that has not appeared for many spins is not due, and a number that has appeared repeatedly is not hot. The only information that matters is the number of pockets on the wheel and the payout for the bet placed.
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