Roulette Rules, Bets & House Edge
European, American and French roulette explained through wheel structure, payouts and zero rules.
The zero pockets create roulette’s house advantage. A single-zero wheel is mathematically more favorable to the player than a double-zero wheel on standard bets.
Wheel types
European roulette normally has numbers 1–36 plus a single 0. American roulette adds both 0 and 00. Some newer variants add other pockets and require separate analysis.
Inside and outside bets
Inside bets cover individual numbers or small groups. Outside bets cover broader categories such as red/black, odd/even or columns. Standard payouts are designed around 36 non-zero numbers even though zero pockets are also possible outcomes.
Single zero versus double zero
On a standard single-zero wheel, a straight-up 35:1 payout on one number produces a house edge of about 2.70%. On a standard 0/00 wheel it is about 5.26%.
La Partage and En Prison
On some French or European rules, even-money wagers receive special treatment when zero occurs. These rules can reduce the effective house edge on qualifying bets.
Streaks do not change the wheel
A sequence of reds does not make black mathematically due on an independent spin. Betting systems can change the pattern of wins and losses but not the underlying expectation.
Why standard payouts create the edge
A straight-up roulette bet pays 35:1 even though a fair net payout would be 36:1 on a 37-pocket single-zero wheel and 37:1 on a 38-pocket double-zero wheel. The zero pocket or pockets are therefore part of the price.
Rule variants must be isolated
La Partage and En Prison apply only under specified conditions and generally affect eligible even-money bets, not every wager on the wheel. Triple-zero or other nonstandard wheels require separate mathematics.
Reference data
The roulette probability table and Casino Mathematics Dataset preserve wheel type, payout and house-edge context so values are not detached from the rules that produce them.