Di En Prison rule inna roulette
“Inna prison”: wen zero ketch a even-money betbet demEven-money betRed/black, odd/even, high/low. 18 numba, pay 1:1.Read di whole ting →, it get one more spin insteada fi lose.

Inna en prison roulette dem hold yuh chip; if di nex spin win, yuh get back di stake (no winnins). Inna di maths it close to la partage: bout 1.35% edge.
Ow it go
Zeropon di wheelZeroDi one green pocket weh no even-money, dozen or column bet nuh cover; a weh di house edge come fram. Nex name: single zero, 0.Read di whole ting → play. Dem nuh sweep weh yuh $10 redbet demRedEven-money bet pon di 18 red numba. Inna French: rouge.Read di whole ting → chipmoney mattaChipA token weh stand fi a fix amount, weh yuh put pon di betting layout fi mek a bet. Nex name: check.Read di whole ting →; di dealer put a marker pon it, or slide it pon di line a di box, fi show seh it inna prison. Di nex spin play. Red: dem free di chip an gi yuh back yuh $10, no winnins. Blackbet demBlackEven-money bet pon di 18 black numba. Inna French: noir.Read di whole ting →: yuh lose di chip. Zero again: house rule dem different. Some casino gi back half (dat a la partagerule demLa partageFrench rule: wen zero hit, half a di even-money stake come back. It cut di house edge pon dem bet deh inna half, to 1.35%.Read di whole ting → fi true), some keep it inna prison fi one more spin, an a few tek it straight weh.
Zero play. Dem mark yuh $10 pon red “en prison”.
Dem free di chip. $10 come back, no winnins. Net fi di two spin: $0.
Chip lose. Net: −$10.
It depend pon di house: it stay inna prison, half come back, or yuh lose it.
Di maths
Pon di spin afta zero, di chip inna prison win back it stake wid probabilitymathsProbabilityDi chance fi a result, fram 0 to 1 or 0% to 100%. One numba: 1/37 = 2.70%.Read di whole ting → 18/37 an lose wid probability 18/37 (if wi lef out di second-zero case). Suh it expected valuemathsExpected valueDi average result pon evry bet inna di long run. −1/37 a di stake fi evry standard European bet.Read di whole ting → a bout half di stake, di same like la partage weh gi back half straight weh. If a second zero mek yuh lose di chip, en prisonrule demEn prisonFrench rule: wen zero hit, dem hold a even-money bet fi di nex spin instead a yuh lose it. It cut di house edge pon dem bet deh inna half.Read di whole ting → likkle bit worse dan la partage: 1.39% gainst 1.35%. If a second zero jus keep di chip inna prison fi one more spin, di two a di same ting. Inna di strict French rule, a second zero sen di chip one level deeper, an den it need two win fi come out: 1.37%. Di difference suh small, yuh can ignore it wen yuh a pick a table.
Wah mek di rule deh
Roulette en prison a di older one a di two French rule, an it did deh fi treat di regular dem nice at di spa casino dem inna di 19th century. La partage a di modern, simpla version: same value, no bookkeepin, no argument bout a chip weh lef pon di line. Inna history, di Monte Carlo table dem mek di playa choose wen zero play; today most table jus use one rule automatic.
Ow it mix wid yuh own rule dem
If yuh play wid a stop-lossstrategy demStop-lossA amount a loss weh yuh set fram bifo, an wen yuh reach it yuh end di session (di loss weh mek yuh stop).Read di whole ting → or a fix numba a spin, a chip inna prison a one bet pon di nex spin weh yuh neva choose fi mek. A likkle point, but a di only time inna roulette weh di table mek a decision fi yuh.
Question dem
No. It stay till di nex spin settle it. Some house mek yuh tek half insteada dat, an dat a la partage by anodda road.
No. Only even-money bet, jus like la partage.
Dem di same to within 0.04%. Tek whichever one di table offa.
Fun wid maths
Try dem yuhself fus. Evry ansa fold up; open it wen yuh ready.
Unda en prisonrule demEn prisonFrench rule: wen zero hit, dem hold a even-money bet fi di nex spin instead a yuh lose it. It cut di house edge pon dem bet deh inna half.Read di whole ting →, a even-money betbet demEven-money betRed/black, odd/even, high/low. 18 numba, pay 1:1.Read di whole ting → weh zeropon di wheelZeroDi one green pocket weh no even-money, dozen or column bet nuh cover; a weh di house edge come fram. Nex name: single zero, 0.Read di whole ting → ketch get one more spin: a win gi back di stake, anyting else lose it, a second zero included. Work out di house edgemathsHouse edgeDi part a evry stake weh di casino keep pon average: 2.70% inna European roulette.Read di whole ting →.
Show di ansa
Ansa 19/1,369, bout 1.39%.
Tek $1 pon redbet demRedEven-money bet pon di 18 red numba. Inna French: rouge.Read di whole ting →. It win straight wid chance 18/37: +1.
Zero come up wid chance 1/37. Den di nex spin gi back di stake wid chance 18/37 (net 0) an lose it odda wise. Suh di bet lose wid chance 18/37 pon di fus spin, plus 1/37 × 19/37 afta a zero: 666/1,369 + 19/1,369 = 685/1,369.
Expected valuemathsExpected valueDi average result pon evry bet inna di long run. −1/37 a di stake fi evry standard European bet.Read di whole ting →: 666/1,369 − 685/1,369 = −19/1,369 ≈ −1.39%. La partagerule demLa partageFrench rule: wen zero hit, half a di even-money stake come back. It cut di house edge pon dem bet deh inna half, to 1.35%.Read di whole ting → hand back half one time an cost 1/74 ≈ 1.35%: di second zero a di whole difference.
Sumting fi laugh

Yuh free, but no winnins.
Source dem
- Ethier, S. N. The Doctrine of Chances: Probabilistic Aspects of Gambling.
- Wykes, A. The Complete Illustrated Guide to Gambling.
- Wizard of Odds. “Roulette Basics.”