You are probably aware that casinos increase their house edge over blackjack players by adding more decks to the shoes. Also by adding more decks to blackjack the advantage for card counting to show an effect lengthens, meaning
that counters could go through their bankroll before the advantage is
capitalized on. So why are some casinos going back to single deck blackjack,
why give players and counters this advantage? Have casinos found their hearts?
The answer, as you've probably guessed, is no, they have not!
Most blackjack players have heard that single-deck games offer better odds, so playing with one deck pretty much assures the casino of busy tables. But hidden
in this game is a weapon: blackjacks pay only 6-5 instead of the normal 3-2.
Bet $10 and get a blackjack, and your payoff is $12
instead of $15.
This makes a key difference to the casino house edge, it adds a whole 1.4 percent to the house advantage, which is a big margin. A single-deck game in which the dealer hits soft 17 would normally have a house edge of just
under 0.2 percent.
Take a single-deck game in which the dealer hits soft 17, then have the house pay
only 6-5 on blackjacks, and the house edge against a basic strategy player
soars to about 1.6 percent - nearly five times as high as the house edge in a
good six-deck game.