Sometimes some European roulette games offer a rule known as En Prison which reduces the house edge on the all the even money bets (red/black, odd/even etc). The rule comes into effect when the ball lands on the single zero. Instead of losing all even money bets as would normally be the case they are all "imprisoned". When this happens you get the chance to get your bets back on the next spin. So, your bets will stay in place on the table but notice I said get your bets back, you do actually win anything over and above your initial bets. If on the next spin you get another single zero then you would need two successive bets of whatever even money bet you placed to free your even money bet and have it returned to you.
An example of the rule would be if you bet $2 on red. The ball lands in the single green zero, so for the next round your bet is frozen still on red. If on the next spin the ball lands on a red you get your $2 back. If however it lands on a black you lose your $2.
Sometimes casinos offer a variation of this rule known as La Partage and will offer the player the option of having half the value of there bet returned to them instead awaiting the outcome of the next spin.
The En Prison rule reduces the house edge to just 1.35% so its a huge advantage to the player. Its well worth searching out a table with this rule and going around asking croupiers if the rule is in place as it may not be well advertised.
The surrender rule is sometimes offered on the American double zero roulette wheels. The rule only applies to the even money bets, red/black, high/low, odd/even. When this rule is in place and the ball lands in either the single or double zero pockets half the value of the players bet is returned to them.
An example of the rule would be if you bet $2 on red. If the ball lands in either of the green zeros you get $1 back.
This rule reduces the house edge from 5.26% to a much better 2.63% . Obviously much better odds for the player and similar odds for the standard European roulette. Again ask at different tables to to find out if this rule is offered.
