En Prison and La Partage

When roulette experts recommend single-zero over double-zero games, most inexperienced players automatically assume this is because the former has twice as low a house edge. However, there is one more reason why European and French roulette varieties are better from the perspective of the smart players.

Most single-zero games use two additional rules that are otherwise unavailable at the majority of the American tables. Known as La Partage and En Prison, these rules lead to a further reduction in the house edge.

They apply to even-money propositions only like red/black, odd/even, and high/low. Players frequently refer to the La Partage and En Prison as the “French rules” although you can find them in both French and European varieties of the game. Stick with us to learn what the two rules are all about and how they work to the benefit of roulette players.

Even-Money Bets

1Recover Half of Your Losses with La Partage

If you have read the previous articles from this guide, you sure know the green zero gives the house its edge, which stands at 2.70% in European and French roulette. The zero dilutes one’s chances of winning with all available bet types. However, its negative impact is especially pronounced when one is betting on the outside.

The category of outside bets comprises the dozen and column wagers along with the even-money propositions on number properties. All outside bets are immediate losers when the ball lands in the zero pocket.

The zero does not share the characteristics of any of the even-money bets. It is neither red nor black and has no parity in the context of this casino game. This number is not included in the high/low, column and dozen categories, either.

This is where La Partage comes in handy. The name La Partage translates as “sharing” or “dividing” from French and is a perfect fit for this beneficial rule because it captures its very essence.

Here is how the La Partage works. It kicks in automatically on all red/black, even/odd, and high/low bets when the zero is spun. Instead of losing their wagers in full, even-odds bettors have their initial stakes divided into two halves.

The house keeps only one half of the losing wager. The player gets to keep the other half. This ultimately saves you money if you consistently have even-money bets in play. The La Partage is available at both landbased and online roulette tables that use single-zero wheels. This favorable rule even applies in some live-streamed online versions of the game that are hosted by professional dealers.

2Second Chance for Even-Money Bets with En Prison

The En Prison rule resembles the La Partage in that it also applies to outside bets that deliver even-money payouts when successful. The meaning of the French phrase is again indicative of what the rule stands for as it translates as “in prison”.

So, how is En Prison different from La Partage? When the ball settles in the green pocket at single-zero tables, even-money bets do not lose right away but get a second chance instead. The dealer places a marker on top of the even-money propositions instead of immediately raking the chips off the layout.

The marker indicates these bets are “imprisoned” for the next round of play. If the bet wins the second time around, the dealer returns the player’s original stake in full instead of paying them at even odds of 1 to 1. This way the player breaks even, neither winning nor losing money to the green zero.

3Example of the En Prison rule in action

Let’s imagine you have a $10 bet on even numbers. The ball finds its way into the green-zero pocket and your dealer places a token on top of your $10 bet to mark it as imprisoned. Several scenarios can occur afterward:

  • Zero is spun again and you lose your $10 bet irrevocably.
  • The ball lands on one of the 18 odd numbers and you lose the $10 you initially wagered on the opposite outcome, even.
  • One of the 18 even numbers shows, in which case the dealer simply removes the En Prison token from your chips and gives you back your original $10. You can leave the chips on the layout and again bet on even or use them to post another type of wager.

Depending on the policies of the particular casino you play at, your bet may remain imprisoned if zero hits twice in a row. The player’s initial bet must win once to get out of the double imprisonment and return to its original En Prison position. If the bet wins again, the player receives their initial stake in full.

If the opposite even-money outcome occurs in between spins, you lose your money. On very rare occasions would casinos offer triple or even quadruple imprisonment when several consecutive spins of zero occur. Of course, the probability of zeros hitting three, four or more times in a row is minuscule.

So far, we have not come across online variations of roulette to offer En Prison on even-money bets. To our knowledge, it exists only in landbased games that play under the European rules and is rarer than the La Partage.

Cutting Down the House Edge with the French Rules

How the House Edge Changes

The Surrender Rule – La Partage's Equivalent in American Roulette

Since even-money bets are granted a second chance under the En Prison rule and players get half of their losing stakes under the La Partage, it makes sense that the presence of these rules is extremely favorable for the even-odds bettor.

As previously explained, single-zero roulette offers a relatively tolerable house edge of 2.70%. The La Partage cuts this percentage in half to 1.35%. In effect, this renders even-money propositions in roulette just as decent an option from a house-edge perspective as the don’t pass/don’t come bets in craps (1.36%) and the player bet in baccarat (1.24%).

It should be specified that the edge reduction to 1.35% is at hand only if you play the even-money outside bets. The house edge for all other available bets stands at its usual 2.70% because the French rules are not in force for the rest of the wagers, even if they end up losing to zero.

Things get a little trickier with the En Prison, though. It also yields an advantage of 1.35% for the casino, but only on condition the bet remains imprisoned only once and loses if zero is spun for a second time. Matters are more complicated when the casino allows for multiple imprisonment levels upon consecutive spins of zero.

The positive impact of En Prison decreases progressively with each level of imprisonment. This results from the decreasing probabilities of the zero turning up on multiple successive spins. Any individual number, zero included, stands a 2.70% chance of making an appearance during any given spin of the single-zero wheel. The percentage drops to 0.073% for two successive spins of zero, to 0.0019% for three successive spins, and so on. You get the picture.

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