La Partage and En Prison Rules

The Rules That Change the Math

French roulette includes two optional rules—La Partage and En Prison—that apply when the ball lands on zero. Both rules reduce the house edge on even-money bets from 2.70% to 1.35%. For serious players, they're the most valuable rules in roulette.

La Partage: Half Back When Zero Hits

La Partage means "the sharing" in French. When the ball lands on zero, even-money bettors (red/black, odd/even, high/low) receive half their stake back automatically.

Example: You bet €50 on red. The ball lands on zero. You receive €25 back. Your net loss is €25 instead of €50.

Over time, recovering half your bet on zero spins halves the house advantage on those bets. The math: with one zero and 37 pockets, the house edge normally comes entirely from the zero. La Partage returns half of that loss, cutting the edge to 1.35%.

En Prison: Your Bet Gets Another Chance

En Prison means "in prison." Instead of losing half immediately (La Partage), your entire bet is "imprisoned" on the layout for one more spin.

If you win the imprisoned spin: your original stake is returned (no winnings). If you lose the imprisoned spin: you lose your stake normally.

The expected value of En Prison equals La Partage exactly—both produce a 1.35% house edge. En Prison is higher variance (you might win your full stake back vs guaranteed half return) but identical in long-run expectation.

Which Tables Offer These Rules?

La Partage and En Prison are standard at:
• Traditional French casinos (Monte Carlo, Cannes, Deauville)
• Premium European casinos that offer French roulette tables
• Many online casinos with dedicated French roulette games

American casinos almost never offer these rules. British casinos often have La Partage on their single-zero tables.

Why This Matters Practically

If you play 100 spins at €25 per spin:

• American roulette: Expected loss = €25 × 100 × 5.26% = €131.50
• European roulette: Expected loss = €25 × 100 × 2.70% = €67.50
• French roulette with La Partage (even-money only): Expected loss = €25 × 100 × 1.35% = €33.75

La Partage cuts your expected losses to one-quarter of American roulette. The difference is meaningful over any sustained session.

Combining Rules for Maximum Value

The optimal roulette setup: French wheel, European layout, La Partage or En Prison on even-money bets. If you must play American roulette, at least stick to even-money bets, though the double-zero still extracts significantly more.