Should You Ever Split a Pair of 10s?

You've been dealt a pair of 10s, and a little spark of excitement goes off in your head. It feels like a jackpot. It seems like the perfect opportunity to double your chances of winning by splitting them into two separate hands.

The question of whether to split a pair of 10s has been a topic of debate for decades, with early blackjack authors like John Scrane and Edward Thorp even suggesting it under specific circumstances. But modern, computer-simulated basic strategy has provided a definitive answer. The short and absolute answer is: No.

While splitting pairs is a key part of basic strategy for some hands, splitting a pair of 10s is a costly mistake that will lose you money in the long run.

The Power of a Hard 20

A pair of 10s gives you a hard 20. In blackjack, a total of 20 is the second-best hand you can be dealt, right behind a natural blackjack (21). A 20 is a powerful hand that wins a majority of the time, and the only way you can lose is if the dealer also has a 20 or, even worse, a blackjack.

When you have a hard 20, you are in an incredibly strong position. The mathematically correct move is to simply stand and wait for the dealer to play out their hand. Your odds of winning are extremely high, and you want to capitalize on that advantage.

The Math Behind Why You Should Never Split

When it comes to the question of should you ever split a pair of 10s, the math is clear. Splitting your hand might seem like you are increasing your chances, but you are actually decreasing your expected winnings. By splitting, you are breaking up a nearly guaranteed winning hand for two hands that have a high chance of being worse.

Let's look at the numbers. When you split your two 10s, you start with two hands, each with a value of 10. The goal is to get two hands of 20 or higher, but the odds are not in your favor.

• Outcome 1: Your new hand with a 10 is dealt another 10-value card. You now have a 20. While this is a great outcome, it's not better than the single 20 you started with.

• Outcome 2: Your new hand with a 10 is dealt a card that's not a 10. If you get a 9, you have a 19 (a worse hand). If you get an 8, you have an 18 (a much worse hand).

In short, you are trading one extremely strong hand for two hands that are likely to be equal or worse in value. The expected value of standing on a 20 is far greater than the combined expected value of splitting the pair.

The Card Counting Exception

Like the insurance bet, the only time splitting a pair of 10s might be the correct move is in an extremely rare card-counting scenario. If a card counter knows the deck is rich with Aces and 2s and has a negative count of 10-value cards, it might be a marginally better play. However, for 99.9% of players, this is not a factor. You should never consider this exception.

Conclusion

The next time you are dealt a pair of 10s, suppress the urge to split them. By standing on your hard 20, you are making the mathematically correct move that gives you the highest chance of winning. A pair of 10s is a powerful gift don't throw it away.

In conclusion, should you ever split a pair of 10s? The answer is a resounding no.

Additionally, be aware that splitting a pair of 10s is often frowned upon by other players at the table. While it's your money, many players believe that breaking up a 20 is a move that negatively affects the flow of cards for everyone. Sticking with the winning move is not just smart it's also considered good blackjack etiquette.