The rules of blackjack differ slightly in the various land casino locations in the world. There are minor differences in the way that blackjack is even in Vegas Strip, Downtown Las Vegas and Atlantic City. However, there is one major difference in the way that blackjack is played in the land casinos of America and Europe. This difference is the subject of this article. Both versions are available at Australian online casinos like Casino Mate.

In American online blackjack variants the cards are dealt in the following manner – one card face up to the player, one card face up to the dealer, one card face up to the player and one card face down to the dealer. The dealer's face down card is called the hole card. The European online blackjack variant follows the same sequence for the first three cards. The dealer’s face down card is not dealt. Hence this online blackjack variant is known as a 'no hole card' game.

In American online blackjack variants the hole card comes into play under certain circumstances before the player makes any move. If the dealer's face up card is an ace or a ten value card he checks the hole card for blackjack. The player cannot see the hole card. If the dealer has a blackjack then the players lose their bets. The exception is that if the player also has a blackjack then the bets push. Otherwise, the players make their moves secure in the knowledge that the dealer does not have a blackjack.

In European online blackjack variants even if the dealer's face up card is an ace or ten value card, he cannot check for blackjack. The players start making their moves immediately with the possibility that the dealer may ultimately get a blackjack. The dealer’s second card will be dealt face up after the player completes all his moves.

The difference in the hole card rule is not simply cosmetic. It has an impact on optimum blackjack strategy. In blackjack the player can under certain circumstances make moves like split and double that involve placing additional wagers. In American online blackjack variants these moves are made after the dealer checks for blackjack, if required, but before the player makes any other move. If the dealer has a blackjack then the player loses immediately and will be saved from making split or double moves and losing additional amounts. In European online blackjack the dealer cannot check for blackjack even if he has an ace or ten value card face up. So the player is always under the threat of the dealer getting a blackjack. Hence optimum blackjack strategy says that the player should be more conservative in these circumstances and use the split and double moves sparingly.