Why Single Deck Blackjack Isn’t Such a Great Game to Play Anymore?

Single deck blackjack is a game highly sought after by players the world over.  It is renowned for its fairness to the players because it is almost an even proposition, with the casino having a very small edge in their favor.

Well – it used to be.  

When you’ve finished reading this guide, you’ll know the single deck blackjack rules, strategy, how the game has changed over the years, and the various odds based on the rules of the game in place.  

The game used to be very much favored by players, especially in the Northern Nevada markets of Reno and Carson City and Las Vegas in the South. It used to be that the single deck dealers from Harrah’s and Harold’s Club in Reno, and The Horseshoe (nowadays known as the Binions Gambling Hall) and The Fremont in downtown Las Vegas were looked upon with great respect by casino management.

And while it is still true that a skilled pitch dealer is a joy to watch (and they are!), the game is no longer such a great proposition.

Why not, you ask?

Essentially there are two reasons.  The first reason is because of this guy:

[Source: www.edwardothorp.com]

His name is Ed Thorp – or more formally, Edward O. Thorp.

He’s the father of card counting, and a former MIT Professor of Mathematics.

He literally wrote the (first) book on card counting, ‘Beat The Dealer’ in 1962.

And went on to become a partner in the first ‘quantitative analysis’ hedge fund, that used an algorithm-based investment strategy to turn an initial investment of $1.4 million into $273 million.

In short – he’s always one of the brightest guys in any room he happens to be standing in.

The other is how the casinos responded to his book, and the slew of others that followed.

But more on that later.

What Is Single Deck Blackjack?

Single deck blackjack is the first blackjack game that was played world-wide.  

As its name states, it uses one deck of cards and follows the standard rules of getting a hand closest to 21, but not going over, and having more than the dealer to win.

Single Deck Blackjack Rules

Common single deck blackjack rules are that the dealer deals two cards to each player and to himself.  

Each casino then puts rules in place to offer the best game for their players, while still maintaining their House Advantage.

The typical rules were as follows:

1. One deck of cards is used for the game, shuffled before the first card is dealt;
2. Blackjack pays 3 to 2;
3. The dealer hits on soft 17;
4. The player can split a hand up to three times to make four hands;
5. Aces can be split once, each Ace gets one card only, and they cannot be re-split or doubled down;
6. A split Ace and a 10-value card count as 21, not blackjack.

The House Advantage (HA) for the casino with these rules was 0.16%.

This is a very good game for the player – with an ‘almost even’ HA. 

Most players at this point didn’t really understand the game, and so the casinos were doing well with their game, because their players would make all kinds of mistakes – not doubling down when they should, splitting at the wrong time, hitting the wrong hands, and so on.

Which was fine until Mr. Thorp’s 1962 book really put the cat among the pigeons.

Because when you add card counting and solid Basic Strategy to that mix, suddenly the game has a negative advantage for the casino.  

And as you can imagine, the casinos were not happy about that.

So what did the casinos do, when faced with losing on a game much-loved by their players?

They did what casinos always do!

There were a few ways they did it.

Added more decks, which increased the HA in their favor.  The more decks in play, the better for the casino.

And they changed the other rules, to make it more in their favor.

And what did that do?  It changed the House Advantage from 0.16, to 1.55%.

What it also did was allow the casino some headroom to change some of the other rules to make the HA not so strong against the player, but it still meant the casino had a massive advantage over the players.

Single Deck vs Multiple Deck Blackjack

Let’s say you’re playing a game that has the following rules:

• Blackjack pays 3 to 2;
• Dealer stands on a Soft 17;
• Double after a split is allowed;
• Double on any first two cards;
• Player can resplit 3 times, into 4 hands;
• Player can resplit Aces; and
• No Surrender

If you’re playing this game on a 6-deck shoe game, the House Advantage, using a cut card is 0.36%.  Obviously the lower the HA the better, but 0.36% isn’t too bad for a player to play against.

What if you could play this game with the same rules, but on a single deck?

Then the House Advantage would be -0.06%.

That’s right!  That minus HA gives the player a small advantage on this game!

So the difference between a single deck game and a multi-deck game with the same set of rules is a reduction in the HA of 0.42%.

No wonder the casinos wanted to play the game on a 6-deck shoe.

Single Deck Blackjack Strategy

Let’s assume that you’ve found a single deck game with a 3 to 2 payout, and some decent rules. 
You decide you’re going to play.

So far, so good.

Here are the two Basic Strategy charts to learn.  One is for when the dealer Hits a Soft 17 (H17), and one is for when the dealer Stands on a Soft 17 (S17).

There are a few differences between the two charts, and all of them are to do with if the dealer has an Ace as their up card.

Basic Strategy Differences Between Hitting and Standing on a Soft 17

The 6 to 5 payout is so strong for the casino that you may find that other rules are included that may not be commonly found simply because the 6 to 5 gives the casino so much leeway with the other rules.

For example, Surrender is rare on a single deck – but it may be offered on a 6 to 5 game.

These two Basic Strategy charts are both ‘Total Dependent’ charts.  This means that the course of action taken is based on the total of the hand.

There is a second set of criteria that can be used, called the ‘Composition Dependent’ hand.  This means that the course of action taken is based on the composition of the hand, and the fewer decks in play, the more impact it may have. 

For example, let’s say you have a Jack and a 6.  You have 16.

Now let’s say you have 4, 4, 5, and 3.  You still have 16, but you may want to make a different hit/stand decision based upon the composition of your hand.

Note that all four of your cards would give you a made hand if you were to hit your 16 with any of them. But they are already gone.  So that impacts your ability to make your hand much more so than having a Jack and a 6, both of which would bust your 16. 

With so few cards to choose from in a single deck game, the decision becomes more critical.

How Does 6 to 5 Impact the House Advantage Given the Same Set of Rules?

What happens now, if given the same set of rules as those listed above, we make the blackjack payout 6 to 5, instead of 3 to 2 and using a cut card?

The House Advantage becomes a monstrous 1.33% - impossible to overcome.

What were the casinos thinking when they put the 6 to 5 rule in place?

Well, here is what I was thinking when I was the VP of Casino Operations at a large casino.  

I was very concerned about the advantage players being able to count the cards on my single deck and get a positive HA against my games.  Talk about inviting trouble!

Secondly, I knew that most retail players didn’t understand the implications of a 6 to 5 payout on blackjack, and still thought of a single deck game as the best game to play even though the 6 to 5 killed any real chance they had of beating the game.

And thirdly, it meant I could respond to the many players requests that I was getting to run a permanent low minimum game on my retail floor, and yet still make my ‘revenue-per-square-foot’ budgeted numbers.

All in all, it was a win-win-win for me.

So initially the casinos put the 6 to 5 blackjack payout in place on their single decks, and allowed the ‘urban myth’ that the single deck is the best game to play to take care of their profit margins. 

It’s been that way since they first introduced the 6 to 5 payout for blackjack a couple of decades ago. 

It’s the very definition of ‘a little learning is a dangerous thing’. 

Nowadays, it’s not uncommon to see the 6 to 5 payout for blackjack on many retail blackjack games in land-based casinos.  

Including the double decks, too!  

(Yes, I’m looking at you Cache Creek Casino near Sacramento!).

Expert Single Deck Advice / Tips

1. Never play a single deck game with a 6 to 5 payout for a blackjack.  You simply cannot overcome the House Advantage on that game.  Even if you’re an expert card counter, it’s just too difficult to do.
2. Never take insurance.  The house edge on insurance is almost 6% on a single deck.  Don’t do it. There is one instance where you might, and that is if you reach the ‘I’m going to win this much and then quit’ amount, and by taking even money you’ve met your goal.  Then it’s okay to do it, but generally, never take Insurance.  And the ‘even money’ hack only works on a 3 to 2 game.  
3. Learn Basic Strategy.  It’s worth the time it takes because it can help you avoid the mistakes that inexperienced players make.  I have included two Basic Strategy charts for single deck earlier in this article.
4. Sometimes you will notice that there is no row for splitting a pair of fives, or fours, or tens.  If there is no row for splitting those numbers, then look up your hand as a hard total.
5. If the rules don’t allow you to split because of a limit on re-splitting, then check the chart for the hard total you have. 
6. If you have a pair of Aces and can re-split them, and drawing to split Aces is allowed, double down against a hard 5 or hard 6, but otherwise just hit.
7. You will sometimes see advice that it’s easier to count cards against a single deck than a double deck.  Counting cards against either is equally simple. Go here for an article on learning to be an expert card counter.  It does take some discipline, but you don’t need to be a math whiz to do it.
8. Manage Your Bankroll.  Go here for some in-depth information about how to manage your bankroll and give yourself a better chance to win when playing single deck blackjack.