When it comes to splitting 10s in the game of blackjack, the bottom line should be:
- Average players should never split and should always stand on 20.
- Card counters will sometimes split in ten-rich decks.
- Smart tournament players will sometimes split when they need to bet more chips, especially if it’s the last hand.
There are two types of blackjack players who split a pair of 10s. The first is the casual player who has no idea what the right playing strategies are for blackjack. The other is the pro who knows the game inside and out. How can splitting tens be bad for the casual player and good for the pro?
WHAT IS A 10 VALUE CARD
In blackjack, a 10-value card could either be a 10, Jack, Queen, or King. A pair of 10s, therefore, could be composed of any two ten-value cards such as:
- 10 plus 10
- Queen plus 10
- Jack plus King
- Jack plus Queen
PLAYING OPTIONS FOR PAIR OF 10S
There are only two viable playing options when you are dealt a pair of 10s:
If a player stands with a pair of 10s, he has a 20; if he splits, he is playing two hands, each starting with a 10.
Some land-based and online casinos allow players to resplit up to a maximum of three or four hands; therefore, if a player were to split 10s and draw another 10 to either split hand, he would have the option to split again to create three (or four) hands, each one starting with a 10.
When playing blackjack against the dealer, most casual players split 10s when he has a weak upcard like a 5 or 6 (although I have seen many players during my career split 10s no matter what the dealer shows). Their logic for splitting on the dealer’s 5 or 6 goes something like this: “The dealer has a weak card and I’ve got a good chance to make two good hands starting with a 10 so why not split and double my winnings.” Oh, really.
Let’s look at your expected value, or the average amount you would win per hand when you stand on your 10s compared to what you win when you split against the dealer’s upcard of 5. (Note: The following analysis is based on a typical six-deck game, where the dealer stands on soft 17.)
- When you stand on your pair of 10s, you will win 83% of the time and lose 17% of the time. That’s not too surprising because it’s tough for the dealer to beat a strong hand of 20.
- If you split the 10s one time, you stand to win 63% and lose 37% on each split hand. That’s a significant decrease in the number of hands won simply because if you split, you will often end up with less than 20 on both hands.
This means that for an original wager of, say, $10, after 100 hands this is what you would net on average:
- Standing will get you a $660 profit
You will win $10 x 100 hands x .83 = $830
You will lose $10 x 100 hands x .17 = $170
Your net profit is $830 – $170 = $660
- Splitting the 10s will net you $520
You will win $10 x 100 hands x .63 = $630
You will lose $10 x 100 hands x .37 = $370
Your net profit is $630 – $370 = $260 per hand
Since you are playing two hands when you split the 10s, your net overall profit would be twice the $260 profit per hand, or $520
The above analysis shows that when you stand on a pair of 10s vs. splitting them against a dealer 5 upcard, you figure to win $140 more when you stand vs. when you split.
$660 profit when standing – $520 profit when splitting = $140
Note: A similar analysis can be done for any dealer upcard and any mix of playing rules and number of decks of cards being used and you’ll always arrive at the same result: for a basic strategy player who is not card counting, standing on a pair of 10s is always a more profitable play than splitting. Also, keep this in mind: Since splitting 10s is a bad strategy, then resplitting 10s is an even worse strategy, so never do it.
WHEN TO SPLIT 10S
There are two instances where splitting 10s should be considered. The first occurs when there is an excess of 10s in the unplayed cards making it more likely that you will draw a 10-value card to each split 10 giving you two hands of 20.
The only way you would know if the unplayed cards are rich in 10s is by card counting. For example, card counters who use the popular Hi-Lo card-counting system will split tens vs. a dealer 5 upcard when the true count (or count per deck) is +5 or greater.
However, even though the latter is the correct mathematical play, splitting 10s in a land-based casino will attract suspicion from casino personnel that you might be a card counter. Therefore, even though it is the correct play, it is not wise to consistently split 10s in a single session.
The second instance where splitting 10s could be considered occurs in the last hand of blackjack tournaments where the goal is to have more chips than your fellow table players after a set number of hands are played. For example, if it’s the last round and winning the hand with the chips that you’ve bet will still not be enough to overtake the leader, but betting twice as much will do the job, then a player should consider splitting the 10s.
What follows is an example of how this worked for me once in a tournament.
The table leader had $2,000 more than me going into the last hand. He bet first and made a $5,000 max bet. I matched his bet and put out $5,000. At this point I knew that if he won his hand and I won my hand, I would have been eliminated (because he’d still be ahead of me by $2,000). Therefore, I had to bet more to have any chance to overtake his $2,000 lead, and the only way to do that was to either pair split or double down (I still had $5,000 in unbet chips to use for a pair split). The leader had an 18 and stood. Fortunately, I was dealt of pair of queens so I split them, made another $5,000 bet, and fortunately drew two picture cards and stood with my two 20s. The dealer subsequently busted, and I won the round and advanced because I won $10,000 on the last hand while my opponent won only $5,000 (i.e., I had $3,000 more than he had at the final chip count).
The above scenario is an example of why splitting 10s in tournaments is sometimes a smart play, especially when you need to bet more money to beat an opponent. You’ve got to remember, however, to split your bankroll in half before you bet, otherwise, you won’t be able to pair split. (Unlike doubling down, you can’t pair split for less.)
For more information on land-based and online blackjack playing strategies, including playing and betting strategies in tournaments, consult Chapter 10 and Chapter 15 in the Ultimate Blackjack Strategy Guide.