La partage and en prison: the rules that halve roulette losses on zero
La partage returns half of an even-money bet when the ball lands on zero. En prison holds the bet for one more spin instead. Both cut the edge on even-money bets from 2.70% to about 1.35% on a single-zero wheel.
Reviewed Oct 14, 2026
Answer first
90s| Wheel and rule | Edge on even-money bets | Edge on other bets |
|---|---|---|
| Double zero, no rule | 5.26% | 5.26% |
| Double zero, half-back (Atlantic City) | 2.63% | 5.26% |
| Single zero, no rule | 2.70% | 2.70% |
| Single zero, la partage | 1.35% | 2.70% |
| Single zero, en prison | About 1.35% | 2.70% |
Key numbers
Half-back rules in four numbers
In short
Key takeaways
- The rules only help even-money bets: red, black, odd, even, 1–18 and 19–36.
- Inside bets, dozens and columns keep the full edge.
- Atlantic City casinos give half back on even-money bets when 0 or 00 hits.
- A single-zero wheel with la partage is the cheapest roulette bet you can find.
On the wheel
What happens when zero hits
Zero
La partage: half of a $20 red bet comes back
Red bet
Wins 18 of 37 spins on a single-zero wheel
Straight-up on 17
Loses in full on a zero; no rule applies
Half-back rules cut the loss on zero for even-money bets only.
Cost of 100 spins at $10 on red
| Wheel | Expected loss |
|---|---|
| Double zero | About $53 |
| Double zero, half-back | About $26 |
| Single zero | About $27 |
| Single zero, la partage | About $14 |
Averages only. Real sessions swing far more.
How en prison works
With en prison, a zero locks your even-money bet for the next spin. If that spin wins, the bet is released and returned without profit. If it loses, the bet is gone.
Some casinos keep the bet in prison again on a second zero. The edge stays close to 1.35% either way.
Sequence
Finding a better roulette table
Step 01
Count the greens
One green pocket is better than two.
Step 02
Ask about zero rules
"Do you have la partage or surrender?"
Step 03
Bet even-money spots
Only they get the half-back.
Step 04
Check the minimum
Better rules often mean a higher minimum.
Where to find the rules
In the US, Atlantic City casinos must give half back on even-money bets when zero or double zero hits. That halves the 5.26% edge.
Las Vegas offers single-zero tables in some high-end pits, and a few spread la partage. They often carry higher minimums.
Choosing your bets
If a table offers la partage, even-money bets become the best value on the layout. A $10 red bet costs about 13 cents per spin on average.
The same $10 on a straight-up number costs 27 cents, twice as much.
Floor rules
Rule terms
Know before you sit
- La partage
- Half of an even-money bet is returned when zero hits.
- En prison
- An even-money bet is held for one more spin after a zero.
- Surrender
- The Atlantic City half-back rule on 0 and 00.
- Even-money bet
- A bet that pays 1 to 1.
A night at a la partage table
Bet $25 on black for 200 spins on a single-zero wheel with la partage. That is $5,000 in action.
The expected loss is about $68. Without the rule it is about $135, and on a plain double-zero wheel about $263. The wheel and the rule matter more than any betting system.
Common mistakes
- Expecting the rule on every bet
- Half-back rules cover only even-money bets. A split or corner bet loses in full on zero.
- Ignoring the wheel type
- A double-zero wheel with half-back still costs about the same as a plain single-zero wheel.
- Not asking
- The rule is not always on the sign. One question to the dealer tells you.
- Moving the bet in prison
- A bet held in prison cannot be removed or changed until the next spin settles it.
Keep reading
Related pages
Go play
Where to play in Las Vegas
Tap a resort — each row opens that casino’s White Gambling page (hours, game mix, floor facts). Venues with this game in official counts, sorted high to low.
Open a casino page
Real listings · not adsAfter the 90 seconds
Questions before and after you play
A 90-second guide cannot cover every table moment. Tap a group, then a question — answers are short paragraphs, not one-liners.
01Rules
What is la partage in roulette?
A rule that returns half of an even-money bet when the ball lands on zero. It cuts the edge on those bets in half.
What is en prison?
A rule that holds an even-money bet for one spin after a zero. If the next spin wins, you get the bet back without profit.
Which is better, la partage or en prison?
They cost almost the same, about 1.35%. La partage is simpler because the result is settled at once.
02In the US
Does Atlantic City use la partage?
Atlantic City casinos give half back on even-money bets when 0 or 00 hits. On a double-zero wheel, that lowers the edge to 2.63%.
Can I find la partage in Las Vegas?
A few high-limit and European-style tables offer it. Most Vegas wheels have no zero rule.
Is the rule used online?
Some licensed online casinos offer French roulette with la partage. The game rules screen shows it.
03Value
Which roulette bet has the lowest edge?
An even-money bet on a single-zero wheel with la partage or en prison, at about 1.35%.
Does the rule help inside bets?
No. Straight-ups, splits, streets and corners keep the full edge of 2.70% or 5.26%.
Is roulette with la partage as good as blackjack?
It is close to basic strategy blackjack at a good table, which runs about 0.5% to 1%.
Sources
- Wizard of Odds — Roulette Not from a registry (Reference source, not an official registry)The gaming industry’s standard reference for casino-game math, by actuary Michael Shackleford. Not an official registry; our calculators compute these numbers independently. · accessed Oct 14, 2026Rules, odds and house edge
- New Jersey Division of Gaming Enforcement · accessed Oct 14, 2026Table game rules in Atlantic City
- Nevada Gaming Control Board · accessed Oct 14, 2026Approved games and gaming revenue reports
- National Council on Problem Gambling — Help and resources Not from a registry (Reference source, not an official registry) · accessed Oct 14, 2026Free, confidential help: call or text 1-800-GAMBLER