Soft 17 Rule
by Henry Tamburin
"I played blackjack in a casino and noticed that whenever the dealer had a soft 17 hand, he would take a card. I thought dealers were supposed to stand on 17."
As a general rule, casino rules specify that dealers must draw on "16 or less" and stand on "17 and more". In fact it states that right on the layout. However, when the dealer's 17 contains an ace that is counted as 11, the hand is known as a soft 17 (e.g. Ace, 6 or Ace 2, 4 are soft 17's). And in some casinos, the rules specify that dealers must hit their soft 17 rather than stand and it will state that on the layout (this is known as the soft 17 rule).
So what's the big deal you say. Does it really make a difference on that one hand whether or not the dealer stands or hits? Well it is a big deal because that one slight rule change increases the casino's edge over players by about 0.2%.
The reason that the player's expectation decreases when the dealer must hit soft 17 is that even though the dealer will bust slightly more often when he hits compared to standing on 17, the times he doesn't bust he will more often end up with a hand that totals higher than 17. The net result is the casino's edge increases by 0.2%.
Your best bet is to not play blackjack in casinos that have the soft 17 rule especially when 6 decks of cards are used. But if you have no choice, then you should modify your basic playing strategy on these three hands (for a typical 6-deck game). They are as follows:
Double down on 11 (e.g. 6,5) against dealer's ace upcard (instead of standing)
Double down an soft 19 (Ace, 8) against dealer's 6 upcard (instead of standing)
Double down on soft 18 (Ace, 7) against dealer's 2 upcard (instead of standing).
Sometimes new casinos come under a lot of heat from blackjack players when they implement the soft 17 rule at their blackjack tables. This was the case in a new Mississippi casino that opened with this player unfavorable rule. Critics (myself included) and players voiced their discontent loud and clear especially since most of the other near bye casinos did not have this rule. It didn't take long before the casino changed the rule to "dealer's standing on soft 17" and took out ads in local papers to announce the change.
The soft 17 rule historically has been part of the blackjack games in the downtown Las Vegas and Reno casinos. Here you'll find mostly the more player favorable single deck (vs. 6 deck) blackjack games. The casino's offer the more favorable single deck games but then take some of that player advantage away by implementing the soft 17 rule. But still a single deck game with the soft 17 rule is a better game for most blackjack players than a typical multiple deck game.
The following chart that summarizes the effect of the casino's advantage over the basic strategy player when the soft 17 rule is in effect (i.e. dealer must hit soft 17). H17 =dealer hits soft 17. S=17 means dealer stands on soft 17. DAS=double after pair splitting allowed. NoDAS=doubling after pair splitting is not allowed.
# Decks Rules Casino Edge
1 H17, noDAS 0.18%
1 S17, noDAS -0.01%(Player has the advantage)
1 H17, DAS 0.06%
1 S17, DAS -0.13% (Player has the edge)
2 H17, noDAS 0.40%
2 S17, DAS 0.19%
6 H17, DAS 0.63%
6 S17, DAS 0.41%
You can see why casinos that offer single deck games usually implement the soft 17 rule. If they didn't a typical basic strategy player would have the edge. Notice the casino's edge in 6 deck games with the soft 17 rule. Their edge is 0.63% which is fairly high for most blackjack games.
Fortunately in all of the Gulf Coast casinos, the rules specify that the dealer's must stand on soft 17. In the Tunica based casinos, currently all the casinos hit soft 17 except the Isle of Capri and the Grand (the Grand has a mix of hit and stand soft 17). The casinos in Tunica compensate for the hit soft 17 rule by offering more player favorable single deck games then the casinos along the Gulf Coast.
The bottom line is that the soft 17 rule is palatable in single deck games, but with 2 and 6 deck games you should try to play in casinos where the rules specify that dealers must stand on soft 17. That's the smart way to play blackjack.
Dr. Henry Tamburin is one of America's most popular casino gaming writers
and the author of 6 best-selling casino books including his Blackjack: Take
The Money & Run. For a free copy of Tamburin's Blackjack Insider Newsletter
visit his web site at www.smartgaming.com. For a free copy of Tamburin's Casino
Gambling Catalog call 1- 888- 353-3234.