What the rules do
Both soften the zero, and both apply only to bets paying 1:1: red/black, odd/even and high/low. Nothing else on the table benefits.
La partage ("the sharing"): when zero lands, you lose half your stake and the other half is returned immediately. The hand is over.
En prison ("in prison"): when zero lands, your whole stake is held on the table for one more spin. If that spin wins, the stake is returned with no winnings. If it loses, the stake is gone.
Why they are not the same number
They are quoted almost everywhere as both being 1.35%. That is right for one of them.
La partage halves the loss on zero, so it halves the edge exactly: 1/74 = 1.3514%, precisely half of the European 1/37.
En prison does something different. It does not return half; it risks the whole stake on one more spin, and that stake survives only 18 times in 37. Working it through gives 19/1369 = 1.3879%.
| Rule | On zero | Exact edge | Percentage |
|---|---|---|---|
| La partage | Half the stake returned at once | 1/74 | 1.3514% |
| En prison | Stake held for one more spin | 19/1369 | 1.3879% |
| No zero rule (European) | Stake lost | 1/37 | 2.7027% |
| No zero rule (American) | Stake lost | 1/19 | 5.2632% |
The gap is small, about four hundredths of a percent, but it is real and it runs the direction most people assume it does not. La partage is the better rule.
One caveat that explains the confusion: some houses allow a stake to be imprisoned twice, or return half of an imprisoned stake on a second zero. Under those variants en prison converges toward la partage, which is presumably how the two came to share a figure in print.
Where to find them
La partage is standard on French tables and appears on some European tables, particularly at higher limits. En prison is more common in the United Kingdom and parts of continental Europe. A few American casinos run a single-zero table with la partage, and where they do it is comfortably the best roulette in the building.
Ask before you sit. The rule is not always signposted, and it is worth more than any bet selection you will make all night. Our page on European against American wheels covers the other half of the same decision.
Frequently Asked Questions
- Is la partage better than en prison?
- Slightly, yes: 1.35% against 1.39%. La partage returns half immediately, while en prison risks the whole stake on one more spin.
- Why do most sites say both are 1.35%?
- Because they treat the rules as equivalent. La partage is exactly 1/74, or 1.3514%. Standard en prison works out at 19/1369, or 1.3879%.
- Which bets do these rules cover?
- Only even-money bets: red/black, odd/even and high/low. Dozens, columns and all inside bets pay the standard 2.70%.
- Is French roulette the cheapest casino game?
- An even-money bet under la partage at 1.35% is among the lowest-edge bets available anywhere, beaten mainly by full-pay video poker and correct-strategy blackjack.
House edges on this page are computed from the pocket count and the payout in exact rational arithmetic, then checked against published references before publication. Payouts are standard, but the wheel and the zero rule vary between casinos and between tables in the same casino, so confirm both before you sit down.