Definition
Outside Bet
Also known as Outside Bets, Even Money Bets
By Abhinav VasudevanReviewed Editorial policy
In short
An outside bet in roulette covers a large group of numbers, red, black, odd, even, dozens or columns, paying 1:1 or 2:1. The house edge is identical to inside bets; only the volatility is lower.
Outside bets are placed in the boxes around the number grid. They cover many numbers and pay little.
The bets
| Bet | Numbers | Pays | Win chance (European) |
|---|---|---|---|
| Red / Black | 18 | 1:1 | 48.65% |
| Odd / Even | 18 | 1:1 | 48.65% |
| High (19–36) / Low (1–18) | 18 | 1:1 | 48.65% |
| Dozen (1–12, 13–24, 25–36) | 12 | 2:1 | 32.43% |
| Column | 12 | 2:1 | 32.43% |
The zero is why they are not 50/50
Red/black pays even money and covers 18 of 37 pockets, 48.65%, not 50%.
The zero belongs to neither red nor black, neither odd nor even, neither high nor low. It is the only difference between the payout and a fair bet, and it produces exactly the 2.70% house edge that applies everywhere else on the table.
Where outside bets become genuinely better
This is the one case in roulette where a bet type is mathematically superior, and it is worth knowing.
On a French table with La Partage, a zero returns half your even-money stake. With En Prison, the bet is held for one more spin.
Either rule halves the house edge on even-money outside bets to 1.35%. The best odds available on a roulette table, and better than most games in the casino.
Crucially, these rules apply only to the even-money bets. Dozens and columns still carry the full 2.70%.
Systems live here
Outside bets are where progression systems are played, because they win close to half the time. Martingale doubling on red is the archetype.
It does not work, for the reasons set out under table limits: the ceiling and your bankroll both terminate the sequence, and the expected value of each individual spin is unchanged by whatever happened before it.
Common questions
Is red or black a 50/50 bet?
No. Red covers 18 of 37 pockets on a European wheel, which is 48.65%. The zero belongs to neither colour, and that single pocket is the entire house edge. The payout is even money; the proposition is not.
Which outside bets benefit from French rules?
Only the even-money ones: red/black, odd/even and high/low. Dozens and columns still carry the full 2.70%. On a La Partage table the even-money bets are genuinely better than everything else on the felt.