European vs American roulette: why the extra 00 nearly doubles the edge
Short answer — A European wheel has 37 pockets (1 to 36 plus one zero). An American wheel has 38 (1 to 36, a zero and a double zero). Because the payouts stay the same, the extra pocket changes the house edge from 2.70% to 5.26% on a standard red/black or straight-up bet. In pesos, PHP 10,000 of even-money or straight-up bets loses about PHP 270 on a European wheel and about PHP 526 on an American wheel, on average. Those are long-run expectations, not forecasts for one session.
This guide shows where the figures come from, why the five-number American bet is worse again, and what to check on the wheel you are playing. Sources are linked next to each fact. Figures marked as our calculation were worked out from the pocket counts and payouts. Sources were checked on 15 October 2026.
The arithmetic behind 2.70% and 5.26%
The house edge is the expected value of one unit bet, taken as a negative number. Wikipedia’s roulette article gives the two standard calculations: on an American wheel a single number wins with probability 1/38 and pays 35 to 1, so the expected value is −1 × 37/38 + 35 × 1/38 = −0.0526, a 5.26% edge; on a European wheel the single number wins with probability 1/37, so the expected value is −1 × 36/37 + 35 × 1/37 = −0.0270, a 2.70% edge (Wikipedia, Roulette, house edge).
Our check: the even-money red/black bet on a European wheel wins 18 of 37 pockets and pays 1 to 1, giving 18/37 − 19/37 = −1/37 = −2.70%. On an American wheel it wins 18 of 38 pockets, giving 18/38 − 20/38 = −2/38 = −5.26%. The extra pocket does not change the payout, only the chance of losing, and that is why the edge doubles.
| Bet | Pays | Winning pockets | House edge | Expected loss per PHP 10,000 |
|---|---|---|---|---|
| Red or black, European | 1 to 1 | 18 of 37 | 2.70% | PHP 270 |
| Straight-up number, European | 35 to 1 | 1 of 37 | 2.70% | PHP 270 |
| Red or black, American | 1 to 1 | 18 of 38 | 5.26% | PHP 526 |
| Straight-up number, American | 35 to 1 | 1 of 38 | 5.26% | PHP 526 |
| Five-number (0, 00, 1, 2, 3), American | 6 to 1 | 5 of 38 | 7.89% | PHP 789 |
The expected-loss column is our calculation: the amount staked multiplied by the house edge. The five-number row follows from the same method: 5/38 chance of winning 6 units, so the expected value is 30/38 − 33/38 = −3/38 = −7.89%.
A worked week of play in pesos
Take a player who puts PHP 100 on red in each of 100 spins, a total of PHP 10,000 staked over a session. On a European wheel the expected loss is 2.70% of that total, about PHP 270. On an American wheel the same play loses about PHP 526 on average. The gap, about PHP 256, is the cost of the extra zero for the same amount of play. Over a month of similar sessions, the difference grows in proportion to the total staked.
Real sessions swing far more than these averages. A run of ten reds in a row, or a single lucky straight-up hit paying 35 to 1, can move the result by a large amount in a few spins. The expected value tells you what the wheel takes over many spins; it does not say what you will see in one evening.
What to check on the wheel you are playing
The European and American figures apply to the standard single-zero and double-zero wheels with the standard payouts. Some tables change the rules, for example by returning half of an even-money stake when zero lands (the “la partage” rule), which lowers the effective edge on those bets. Other variants add special bets with their own, usually larger, edges. None of those variants is covered by the figures above.
Before you bet, read the table information for the number of zeros, the payout of each bet and any special rule for zero. Those three settings decide which row of the table applies to you. Our figures assume the wheel is fair, the payouts are as stated, and each spin is independent.
Verified, calculated and not verified
Verified from a published reference: the pocket counts (37 European, 38 American), the 35-to-1 straight-up payout, and the two house-edge formulas giving 2.70% and 5.26% (Wikipedia, Roulette).
Our calculation: the red/black checks, the five-number edge of 7.89%, the expected-loss figures for PHP 10,000 and the chart.
Not verified: the zero rule and payouts of any particular operator’s wheel, and any special rule such as la partage on that wheel. Check the table information before you rely on the figures.
Before you play
Expected loss is the average cost of a bet over many spins, not a prediction. Set a budget and a stopping point before you start, and treat a winning streak as chance, not a pattern. Online gambling in the Philippines is for adults aged 21 and over. Use the operator’s limits and responsible-gaming tools, and follow the rules where you live.
Sources (checked 15 October 2026): Wikipedia — Roulette, house edge and expected-value calculation. The red/black checks, five-number edge, expected-loss table, session example and chart are our own calculation.