Exact model

Winning a roulette bet on red

Probability:
48.6%
Odds:
1 to 1.1
dBan
−0.2 dBan

Bet on red and 18 of the wheel’s 37 pockets win. Under the French half-loss rule, zero returns half the stake.

Calculation

p = 18/37; expected net return = [(18 × €100) − (18 × €100) − €50] / 37 = −€100/74 ≈ −€1.35 per €100

Assumptions

Each of the 37 numbers, including zero, is equally likely. The calculation follows French roulette anglaise rules. The average loss is over repeated plays.

Sources

  1. French casino rules: English roulette payouts Article 55-12, current text checked 26 October 2026
  2. Casino d’Annecy: English roulette rules 37 pockets, payouts, and half-loss on zero checked 26 October 2026