Understanding the En Prison Rule in Roulette
The En Prison rule, which translates from French as 'in prison,' is a specific and highly advantageous rule found primarily in French roulette. It offers players a safety net when they place an even-money bet and the dreaded zero appears. Instead of instantly losing your wager, this rule gives you a shot at redemption on the subsequent spin. For savvy players, finding a table with this rule is a top priority as it drastically improves your odds.
How Does the En Prison Rule Work Step-by-Step?
The mechanics of the En Prison rule are straightforward but must be understood correctly to leverage its benefits. The process only activates under specific conditions:
- Place an Even-Money Bet: The rule only applies to outside bets that pay 1:1. These include Red/Black, Odd/Even, or High/Low (1-18/19-36).
- The Ball Lands on Zero: The trigger for the En Prison rule is the ball landing in the single green '0' pocket.
- Your Bet is Imprisoned: The dealer will place a marker on your wager, indicating it is 'En Prison'. Your stake remains on the table, locked in for the next spin.
- The Outcome of the Next Spin: Two possibilities can occur. If the next spin results in a win for your original bet (e.g., you bet on Red and the next spin is Red), your full stake is returned to you. You don't receive any winnings, but you don't lose your bet. If the spin is a loser (e.g., you bet on Red and Black comes up), your stake is lost to the house.
What happens if the ball lands on zero a second time is subject to casino-specific rules. In some cases, the bet may be 'doubly imprisoned,' while in others it may be treated as a loss.
"The En Prison rule is one of the most favorable rules for a roulette player. It cuts the house edge on even-money bets in half, from 2.7% to a mere 1.35%. This is a statistical advantage you simply cannot ignore."
En Prison vs. La Partage: What's the Difference?
Another player-friendly rule in French roulette is 'La Partage.' While similar, its execution differs from En Prison. Understanding the distinction is key to knowing the table you're playing at.
| Feature | En Prison Rule | La Partage Rule |
|---|---|---|
| Trigger | Even-money bet + ball lands on zero | Even-money bet + ball lands on zero |
| Immediate Outcome | Bet is held ('imprisoned') for the next spin | Player immediately loses half the bet |
| Player Action | Player waits for the next spin's result | Player receives half the stake back instantly |
| House Edge Impact | Reduces to 1.35% on even-money bets | Reduces to 1.35% on even-money bets |
As you can see, both the En Prison roulette rule and La Partage have the same mathematical outcome on the roulette house edge. The choice between them comes down to player preference: do you prefer the suspense of a second spin (En Prison) or the certainty of recovering half your stake (La Partage)?
Why You Should Look for En Prison Tables
The primary advantage of playing at a table with the French roulette rule of En Prison is the reduced house advantage. A lower house edge means you are statistically likely to lose less money over the long term, extending your playtime and increasing your chances of a winning session. This rule is most commonly found on single-zero European or French roulette wheels. It is virtually non-existent in American roulette, which features both a single '0' and a double '00', significantly increasing the house advantage from the start.
Before you sit down to play, always confirm the table's rules with the dealer or check the posted information. Seeking out tables that offer either the En Prison or La Partage rule is a fundamental part of any sound roulette strategy.
