Double after split (DAS)

At an advantage of 0.12% to the player, some casinos will allow the DAS (double after split) rule which gives the player an opportunity to double each bet in return for an extra card to each hand.

Double on 9/10/11 or 10/11 only

Depending on other rules practiced by the house, the double on 9/10/11 rules offers the casino a favorable advantage of between 0.09% for an eight deck game and 0.15% for a one deck game. The double on 10/11 rule offers the casino the even more favorable advantage of between 0.17% of eight decks and 0.26% for a one deck game. This rule allows the player to double down their bet only if they are dealt a total of 10 or 11 initially or more popular in Europe, 9, 10 or 11.