La Partage returns half an eligible even-money roulette stake when zero lands. En Prison holds that stake for a later result, which may release it without a profit or cause it to be lost. Both concern the settlement of particular bets. Neither changes the wheel's probability of landing on zero.
The distinction sounds small until you inspect an account balance. A £10 stake that returns £5, a £10 stake still held on the table and a £10 stake returned without winnings are three different outcomes. This guide explains them with worked examples and shows why the exact zero rule matters more than a table's name.
La Partage and En Prison compared
| Rule | Immediate position | What happens next? |
|---|---|---|
| Standard single-zero settlement | The £10 stake loses. | The bet is finished. |
| La Partage | £5 is returned; £5 is lost. | The bet is finished. |
| En Prison | The £10 stake is held. | A qualifying later result releases the stake without profit; an opposing result loses it. Repeat-zero treatment depends on the rules. |
These are illustrations of the stated rules, not a promise about a particular casino. Before using an online table, read its own help panel. A general review can describe a product family without identifying the exact table, configuration or settlement rule available in your account.
Which bets qualify for La Partage?
The usual qualifying bets are the six even-money selections: red, black, odd, even, low (1–18) and high (19–36). Each covers 18 numbers on a standard single-zero wheel. Zero belongs to none of these selections for settlement purposes, including “even”.
Do not confuse “outside bet” with “even-money bet”. Dozens and columns are also outside bets, but their standard payout is 2:1, not 1:1. The half-stake rule described here does not extend to them. Nor does it cover a straight-up bet on one number merely because it was placed on a French-style table.
The BetConstruct European Roulette rules document explicitly identifies red/black, low/high and odd/even as the even-chance selections receiving a half-stake return on zero in that product. Treat a provider document as evidence for its described game, not permission to assume every roulette title works identically.
A £10 La Partage example
Imagine one £10 bet on red, paying standard even money, with La Partage explicitly enabled. There are three possible types of result:
- A red number: the total return is £20: your £10 stake plus £10 profit.
- A black number: the return is £0, so the net loss is £10.
- Zero: the return is £5, so the net loss is £5.
“Half back” does not mean a £5 win. It means half the original stake is recovered. If your balance was £100 before betting, it becomes £90 when the £10 is committed and £95 when the £5 return is credited, assuming no other activity.
This accounting language helps when reading game histories. Some interfaces distinguish a stake, a payout and a net result; others show fewer fields. Compare like with like before deciding a settlement is wrong.
Why the La Partage house edge is about 1.35%
For this calculation, assume a fair 37-pocket wheel with 18 red numbers, 18 black numbers and one zero. Use a £1 bet on red and standard 1:1 winning profit. The 18 possible £1 wins and 18 possible £1 losses cancel in the weighted average. Zero supplies the remaining expected loss.
Without La Partage: expected net result = (18 × £1 − 18 × £1 − £1) ÷ 37 = −£1/37. The house edge is approximately 2.7027%.
With La Partage: expected net result = (18 × £1 − 18 × £1 − £0.50) ÷ 37 = −£1/74. The house edge is approximately 1.3514%.
The corresponding theoretical return to player is approximately 98.6486% on these eligible bets under these assumptions. It is not the return for every wager on the table. Our RTP explainer covers why a long-run theoretical percentage cannot predict an individual session.
For scale, £100 of qualifying turnover has a theoretical expected loss of about £1.35 under this model. That does not mean someone depositing £100 will lose £1.35. Turnover is the sum of all stakes, which may include money staked again after a return. Actual results can be much better or much worse than the average.
How En Prison settles a held stake
Now imagine the same £10 red bet under an En Prison rule. Zero lands and the stake is retained on the table. If the following result is red, the original £10 is released: there is no additional £10 profit on that held bet. If the following result is black, the £10 is lost.
Keep the original held stake separate from any new bet in your records. A newly placed red bet and an imprisoned red bet can have different payouts on the same red result. One may win normally while the other merely returns its stake.
The harder question is another zero. A guide that stops at “you get another chance” has not fully specified the game. Ask whether the stake remains held unchanged, loses, reduces in value or follows another stated procedure. Also check how unresolved stakes are treated when a session or table closes.
Why En Prison figures can differ
A universal En Prison percentage hides a rule assumption. Consider two mathematical versions, both using the same fair single-zero wheel and ordinary even-money settlement before imprisonment:
- Repeat zero leaves the held stake unchanged: keep waiting until red or black resolves it. The held red stake has an equal chance of eventual release or loss, so the initial bet's house edge is 1/74, approximately 1.35%.
- Repeat zero loses the held stake: after imprisonment, 18 of the next 37 outcomes release it and 19 lose it. The initial bet's house edge is 19/1,369, approximately 1.39%.
These are conditional calculations, not claims that either procedure is offered at a particular UK table. Other rules need their own analysis. For example, the older French-language rules document hosted by Casino 2000 includes specific repeat-zero and closing-session provisions. It illustrates why the full written procedure matters; it is not a source for current UK availability.
There is also a probability trap. On an independent fair wheel, the chance of zero on the next spin is 1/37 even after a zero. The chance of two zeros in a specified pair of spins, considered before either happens, is 1/1,369. Those answer different questions. A zero is not “used up”.
A mixed bet does not get one blanket RTP
Suppose an illustrative round contains £10 on red with La Partage and £2 straight-up on zero at the standard 35:1 profit payout. Total stake: £12.
If zero lands, the red bet returns £5. The zero bet returns £72, comprising £70 profit plus its £2 stake. Combined return is £77 and the net result is £65 after subtracting the £12 originally staked.
That attractive-looking zero result does not eliminate the house edge. The expected loss is £10/74 on the red stake plus £2/37 on the straight-up stake: about £0.1892 in total, or 1.5766% of £12. The extra bet has changed the pattern of outcomes and increased the expected cash loss compared with the £10 red bet alone.
This is why a headline “98.65% RTP” should not be applied to a basket of unrelated wagers. A side bet, multiplier feature or different paytable may require a completely separate calculation.
What to check in an online roulette help panel
- Wheel: confirm whether it has one zero, two zeros or another structure.
- Exact rule: locate explicit La Partage or En Prison wording rather than inferring it from “French”.
- Eligible selections: identify the bets covered and any exclusions.
- Winning payout: check that the stated return or profit matches the calculation you are using.
- Repeat zero: for En Prison, find the full treatment of a second or later zero.
- Settlement record: establish where held stakes, returns and round identifiers appear.
- Other conditions: inspect minimum stakes, rounding, additional features and any applicable promotional restrictions.
Evolution's own roulette overview describes La Partage for its French Roulette variant. That supports the rule description, but a provider's general international page does not establish that every feature or table is currently available through a specific UK operator.
If something is unclear, ask support a concrete question: “On this exact table, what happens to a £10 red bet when zero lands, and what happens if zero repeats?” Save the written answer and game rules rather than relying on a lobby thumbnail.
A lower house edge is not a winning system
Neither rule predicts the next number. Doubling after losses, switching colours after a streak or adding a zero bet does not turn the stated negative expectation into a guaranteed profit. Increasing stakes can also increase losses quickly.
The useful role of these calculations is understanding a product, not deciding that more play is affordable. A smaller percentage applied to much more turnover can still mean greater expected loss. Decide money and time limits independently of a table's RTP, and stop rather than trying to recover losses.
Common questions
Is La Partage the same as cashback?
No. Here it is a game-settlement rule triggered by zero on an eligible bet. A casino cashback promotion has separate terms and may use a different calculation altogether.
Does betting on zero qualify for half back?
No. A straight-up zero bet is a number bet. It settles according to its own payout, not the even-money half-return rule.
Is European roulette always La Partage?
No. A single-zero wheel alone does not establish the rule. Read the specific table's conditions.
Is En Prison always worse than La Partage?
Not under every possible repeat-zero rule. Compare the actual procedure. The two conditional calculations above show why quoting one percentage without the underlying rule can mislead.
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Sources and editorial method
Published 11 October 2026. Prepared with AI assistance using the linked provider and venue documents. Pound examples and probability calculations are original editorial workings using explicitly stated assumptions; they are not results from real-money testing. This article makes no claim about current operator availability and contains no casino affiliate links. Consult the exact game's rules where they differ.