Effects of House Rules on Blackjack Odds

Published: 11/11/2013

Even minor changes in the rules by which blackjack is played can cause major shifts in the advantage held by the House. The most liberal rules may give the casino a margin of just 0.2% or less, making each hand a virtual coin flip. But rules that favour the dealer can put the player at a disadvantage of 2% or more, turning blackjack into a game of chance no better than craps or roulette. Following are the ten most important modifications to be aware of, along with how they affect the House edge.

Number of Decks in Play – Tables typically feature 1, 2, 4, 6 or 8 decks of 52 standard playing cards. Single- and double-deck games are usually dealt by hand with the player’s card face down. Games with four or more decks are dealt face up from a shoe. As the number decks increases, so does the House edge. A double-deck game adds about 0.35% to the House advantage versus a single-deck game. A six-deck game will add another 0.23%. The difference between the six- and eight-deck versions, however, is only about 0.03%.

Dealer Hits or Stands on Soft 17 – This rule is almost always printed on the surface of the blackjack table so that it is easy to tell one version from the other. It is very much to the player’s advantage if the dealer must stand on all totals of 17. If the dealer hits on soft 17, it can increase the House edge by as much as 0.21%.

Player Can Double Down after a Split – By and large, it is to the player’s advantage any time more money can be put into play during a hand. Look for tables where this action is allowed. When the game does not permit doubling down after a split, it increases the House edge by about 0.14%.

Player Can Double on Any Two Cards – Again, the ability to get more money into play helps the player. There are many soft counts that provide good doubling situations, and sometimes doubling on counts of 8 or 9 is the right play. If the table permits doubling down only on counts of 9~11, the House edge rises by about 0.09%. When doubling is restricted to counts of 10 or 11, the edge moves up another 0.09%.

Player Can Resplit Multiple Hands – Generally speaking, the more hands the player can get into play, the better. The optimum rule is to allow splitting up to four hands. If only three are allowed, the House gains an advantage of about 0.01%. If splitting is limited to two hands, the House edge increases by around 0.05%.

Player Can Resplit Aces – This rule is absolutely to the player’s advantage, turning a lousy 2/12 hand into two counts of eleven. If the option to resplit Aces is not available, the House gains an advantage of 0.07%.

Player Can Hit Split Aces – This, too, is a rule that favours the player. If it is necessary to stand on a single card dealt to each split Ace, the House edge goes up by some 0.18%.

Player Loses Only Original Bet Against Dealer’s Blackjack – This is the common procedure for almost all games of 21, but there are a few modifications that assess a penalty whenever the dealer gets a natural blackjack. Those games should most certainly be avoided because they add about 0.1% to the House advantage.

Surrender Rule – Whenever a player agrees to forfeit a hand in return for a refund of half the original bet, the House wins. That’s why so many games offer late surrender, hoping players will lose their nerve. A game without surrender is actually preferable from the player’s point of view because it removes the temptation. When the option is available, it favours the House by about 0.08%. Rather like insurance, the solution is to ignore the offer if it is there.

Blackjack Payout – The trend at casinos of late has been to offer payouts of 6:5 instead of 3:2 for single- or double-deck versions of the game. This rule change can have a devastating affect on the player’s chances of winning, adding from 1% to 1.3% to the House edge. For six- or eight-deck games, the House’s advantage increases by about 1.35%—a huge shift in odds.

Published on: 11/11/2013

Go To bet365
Open Account Offer
Up to £100 in Bet Credits for new customers at bet365.
Min deposit £5 and 1x settled bet requirement to release Bet Credits. Min odds, bet and payment method exclusions apply. Returns exclude Bet Credits stake. Time limits and T&Cs apply.
Comment on this article
Your Name:
Your Email:
What is  + 7