The addition of the extra pocket increases the mathematical odds against a single-number bet to 37/1, but the payout is still only 35/1, which increases the house edge to 5.26%. Of course, the same house edge applies to so-called ‘outside’ bets on combinations of numbers, including red/black, odd/even and so on.īy contrast, double-zero roulette, often known as ‘American’ roulette because of its prevalence in the United States, is played on a wheel with 38 numbered pockets, including a green single-zero and a green double-zero. The true mathematical odds against, say, a single-number bet are 36/1, but the payout is just 35/1, which creates a house edge of 2.7%. As the name suggests, single-zero roulette is played with a wheel consisting of 37 numbered pockets, including a single green zero. Single-zero roulette, also known as ‘French’ or ‘European’ roulette, is the standard, traditional form of the game outside the United States. The simple answer is very favourably, indeed.