The house advantage, or house edge, is the percent of a player’s initial bet that the casino will expect to make in the long run. Flip it around, and it is the amount you would expect to lose. The house has an advantage in every single game – that is how casinos make their money – but not all games are created equal.
Fortunately, blackjack has one of the lowest house edges of any casino game. If we assume a standard game in which is a 6-deck shoe is used, dealer stands on soft 17, the player may double on any first two cards, the player may split up to four times, and the player may double after splitting, the house edge with basic strategy is only 0.4062%. Here, we are assuming the deck is shuffled after every hand.
Thus, over an infinite number of hands, the house will win just 4 cents for every £10 you initially bet. This doesn’t mean that you will never have a winning session, nor does it mean that you won’t have a terrible session sometimes. Anything can happen in the short run. The probabilities are for giant, long-term samples.
When it comes to blackjack’s house edge, one thing to keep in mind is that the number of decks used will alter the house advantage. Single deck blackjack has the lowest casino edge of 0.16%, which gives the player better odds. Double deck games have a considerably low edge at 0.46%. Most land-based resorts and reputable online casinos use six to eight decks for blackjack.
There are dozens of rules variations at different casinos, all of which also change the blackjack house edge. The table below lists just a few that you might see and how they affect the edge. Positive values increase the house edge in blackjack, while negative values decrease the house edge.
| Blackjack Rule Variation | Effect on House Edge |
|---|
| Natural pays 6 to 5 | +1.3597% |
| Dealer hits on soft 17 | +0.2125% |
| Double down on 9-11 only | +0.0961% |
| Eight decks | +0.0266% |
| Four decks | -0.0532% |
| Late surrender allowed | -0.0726% |
To figure out the new house edge with a different blackjack rule, simply take the baseline blackjack house edge and then add or subtract the percentage above. There are loads more rules variants – the above are just a few common ones.
For example, if you find a blackjack table that pays 6 to 5 on a blackjack (a “natural”), run away. The house edge in that game, assuming all other rules are equal, is 0.4062% plus +1.3597% for a whopping 1.7659%. The change in house edge alone is more than three times the original blackjack house edge.
A rule of thumb is anything that pays you less, gives the dealer more flexibility in actions, or gives you less flexibility in your actions increases the house edge.
