What a Wheel Costs Before the Rule
A European wheel has 37 pockets: 1 to 36 plus a single zero. An even-money bet — red, black, odd, even, high, low — wins on 18 of them and loses on 19.
That 2.70% is the same on every bet the layout offers, which is the subject of every roulette bet ranked. Straight up, split, dozen, red — all 2.70%. The zero is the entire house edge, and it takes your whole stake when it lands.
La Partage: Half Back on Zero
Under La Partage — French for "the sharing" — a zero returns half of every even-money stake instead of taking all of it. The rest of the game is unchanged.
Exactly half. That is not a coincidence or an approximation: the entire edge was the zero, and the rule halves what the zero takes.
At 1.35%, an even-money roulette bet becomes one of the better wagers available in a casino — better than every slot, better than baccarat's player bet at 1.24% by only a small margin, and far better than anything on a double-zero wheel.
En Prison: The Stake Is Frozen
En Prison handles the zero differently. Your stake is not returned and not taken; it is locked in place for one more spin. Win that spin and you get the stake back, with no winnings. Lose it and the stake is gone.
This is where published sources diverge, so be precise. Most comparison sites quote 1.35% for both rules. That is right for La Partage and slightly wrong for En Prison, because an imprisoned stake is only rescued 18 times in 37, and a second zero loses it at many casinos. Some houses instead imprison it a second time, which changes the figure again. The rule as modelled here — one imprisonment, lost on a second zero — gives 1.39%. If the table imprisons twice, it is closer to La Partage. Read the table's own rules.
Which of the Two Is Better
La Partage, by 0.04 of a percentage point. On $1,000 staked over an evening that is 40 cents. The practical difference is not the money, it is that La Partage settles immediately while En Prison leaves a stake locked on the layout, unable to be moved, for at least one spin.
Set against the alternatives, though, the gap between the two French rules is invisible:
| Wheel and rule | House edge | Cost per hour, $1 a spin, 50 spins |
|---|---|---|
| La Partage | 1.35% | $0.68 |
| En Prison | 1.39% | $0.69 |
| European, no rule | 2.70% | $1.35 |
| American, double zero | 5.26% | $2.63 |
Choosing between La Partage and En Prison is worth a cent an hour. Choosing between La Partage and an American wheel is worth almost two euros an hour on the same bet, at the same stake, playing identically.
Where to Find Them
The uncomfortable part: this is the only genuine improvement available at a roulette table, and it consists of reading a menu. Every system ever sold — Martingale, D'Alembert, Fibonacci — promises to do what this rule actually does, and none of them can, because they rearrange bets rather than change what a zero costs.
Reality check: 1.35% is still negative. La Partage does not make roulette beatable — it makes it half as expensive on one family of bets. Over a long enough session the wheel still takes the money; it simply takes it at half the rate.
Play with the math on your side
SlotDrop's free tools show you the real house edge, EV and variance behind every bet — before you place it.
Open the Black Box →Reality check: no strategy on this page turns a negative-expectation game into a positive one. Strategy reduces how much the house takes and how fast your bankroll disappears — it does not guarantee profit. Only ever bet money you can afford to lose entirely.