The Soft 17 Rule in Blackjack

Welcome to the guide on Soft 17 blackjack. How the casino decides to play their hand when the dealer gets it tells you a lot about how they feel about their game and their players.  

How you decide to play the hand is a whole different story.

When you have finished reading this guide, you will know how the Soft 17 decisions affect the casino and you, and how you should play your hand in a variety of situations that include the Soft 17.

If you want to learn more about Soft 17 in Blackjack, make sure to watch our video below:

What is a blackjack Soft 17?

A Soft 17 in blackjack is a hand totaling 17 that includes an Ace counted as 11, such as Ace-6. The hand is "soft" because the Ace can still be counted as 1 without busting if another card is drawn. This flexibility makes a Soft 17 less risky than a hard 17.

Here are some examples. All these hands can be either 7 or 17 and contain an Ace.

What is the Soft 17 Rule?

There are two ways to interpret this question.  

1. The first is how does the casino play a Soft 17 
2. The second is how does the player play a Soft 17

From the casino’s point of view

When the dealer gets a soft 17, the choice as to whether to hit or stand has a big impact on the House Advantage (HA). 

It is one of two very important decisions that the casino can make on its blackjack games.  

The other is the number of decks in play – which also affects the HA – but that’s not important here.  

From the player’s point of view

You need to know and use Basic Strategy.

What is Basic Strategy?

It’s how to play your hand in the most advantageous way for you.  

It is the result of billions of hands being played in computer simulations by mathematicians, astrophysicists and blackjack experts and coming up with the best way to play your hand given your cards, and the dealer’s up card. 

I have deliberately not included Basic Strategy charts for single deck blackjack, even though it is generally the best game to play given all other rules are the same.  

The reason is because it’s almost impossible to find a single deck game without a 6 to 5 payout for a blackjack.  

And as you know, you don’t want to be anywhere near a game that pays 6 to 5 for a blackjack as it increases the HA against you by 1.39% - a number that you cannot overcome.

How does Basic Strategy change the way you play?

Let’s take a look. 

Because the most common games to play are Double Deck and a multi-deck shoe (usually either 6 or 8 decks), here are the Basic Strategy charts for both.

Each represents the correct plays if the dealer hits a Soft 17 (H17), or stands on a Soft 17 (S17)

Here are four Basic Strategy charts for how to play when the dealer hits a Soft 17 (H17), and for when the dealer stands (S17) on a Soft 17. 

As you can see, there are some small differences between the two.

It is better to play that against the H17 rules than to play the H17 rules against an S17 game.

First up - Double Deck blackjack Basic Strategy Charts  

A couple of reminders before we go there

• Never take Insurance
• If you see a player’s hand ‘missing’ from the chart – for example, what to do with a pair of 5s, it means you should never split a pair of 5s and to treat the hand as the total, i.e. a hard 10.

How the Soft 17 rule changes the Basic Strategy - Double Deck

Here are the differences between the two Double Deck strategies in table format:

Here are the 4 to 8 deck Basic Strategy Charts

How the Soft 17 rule changes the Basic Strategy – 4 to 8 Deck Shoes

And here are the differences between the two multi-deck strategies in table format:

How the Soft 17 rule affects the House Advantage (HA)

As you know, all the casino games are set up with a built-in advantage to the casino, which is called the House Advantage (HA) or casino edge.  

Does the dealer hit on Soft 17? If so, it increases the casino’s HA by 0.22%.  

Why? Because it will improve their Soft 17 more often than not.

If the casino chooses to stand on a Soft 17, it would reduce the HA by 0.22% versus hitting the Soft 17. 

Things that make you go ‘Hmmmm . . .’

Why would a casino put a rule in place to reduce their HA? 

Because the Table Games Director is putting together a suite of rules that will be most attractive to his players, while still allowing him a competitive HA to ensure he makes his budget numbers at the end of the year. 

So the answer is you’re always going to take another card, either just hitting or doubling down.  

Check the Basic Strategy charts to see if you’re going to hit or double down, which may depend on the house rules for whether they hit Soft 17 or stand on Soft 17, and the number of decks (either double deck or 4 to 8 decks).

And good luck.