Strategy for Splitting Pairs in Blackjack

Most people have heard of blackjack's basic strategy. Alas, few blackjack players take the time to learn basic strategy, which means they'll never be as successful at this exciting casino game as they could be.

Basic strategy in blackjack means learning the best way to play each hand you're dealt. Because a limited number of hands are possible for players competing against a similarly limited number of potential face-up cards for dealers, it's possible to memorize basic strategy from a table or a chart. In many ways, learning basic blackjack strategy is like memorizing multiplication tables or the periodic table of elements.

However, some blackjack players prefer to understand the "why" behind every possible strategic move, so a sterile chart doesn't work so well for them. What's more, a blackjack strategy changes according to the variation of the game and the house rules.

Once a player feels confident in basic strategy, there are special situations that can affect the play. One of the biggest is what's known as the Split, or Splitting Pairs. Ten pairs are possible in blackjack and each pair has a different strategy.

A smart, skilled player will always split aces and eights, no matter what card the dealer has showing. Remember, the basic assumption is that a player will be dealt a 10 on a hit. By splitting aces, a player turns a potential "soft 12" hand into two potential blackjacks. The same is true of splitting eights, since a 16 becomes two hands of 18 by the same logic, which could beat the dealer if the house rule is for the dealer to stand on 17. A pair of aces is the best possible hand for a player to have in blackjack.

By the same token, never split fives or 10s, because no matter what the dealer's up card is, you have more winning potential with these totals. Virtually all basic strategies assume that the player will be dealt a 10 when taking a hit. Splitting fives turns a good hand with a hard 10 count into two stiff hands of 15 each (once again expecting that the player will take a 10 on a hit). Players rarely win with a 15 unless the dealer busts. On the other hand, a total of 10 is good because there are 20 cards in a 52-card deck that will give a total of either 20 or 21. Multiply that probability by the number of decks in play, and it's quickly apparent what an advantage a 10-count hand can be.

Two Basic Rules for Splitting in Blackjack

These two rules sum up nearly half of the possible hands that could be split. Once again:
1.  Always split aces and eights.
2.  Never split fives and 10s.

Now, what about the other cards? Here are some general guidelines, all based on the assumption that the player will get a 10 when taking a hit. Don't forget that basic strategy must adapt to whatever game variation and house rules are in play as well.

General Guideline for Splitting Pairs

Blackjack Splitting Pairs - Twos: Split a pair of twos when the dealer shows 2 through 7 as the up card. Hit the 2s if the dealer shows eight or better.  Expecting that the dealer has a 10 in the hole, the 2-7 strategy gives the dealer 12-17, while the player has 14. There's a good chance of the dealer busting on the 12 through 16, while the player could still outdraw the dealer on a 17.

Blackjack Splitting Pairs - Threes: Split a pair of 3s against the dealer showing 2-7 up; otherwise, take a hit. Most likely a 6 will wind up as a 16 (always assume a 10 as the hit). This is the tough range to play in blackjack, but if the dealer is show an 8 or higher, the player is likely to get beaten anyway. Why lose more money by splitting a pair of 3s into two hands? Meanwhile, a split against a dealer showing 2-7 means the dealer hand most likely will be 12 through 17, so chances are the dealer will bust or the player will outdraw the dealer's 17.

Blackjack Splitting Pairs - Fours: Always keep hold of a pair of fours unless the dealer's up card is a 5 or a 6. A pair of 4s gives a hard total of 8, a good chance of snagging a 10 to make 18 for the final total. That's within winning range. However, if the dealer pulls a 5 or 6 as an up card, she has a greater chance of busting. If a player splits a pair of fours, the best total he or she can hope for is a 14, which wins only if the dealer busts.

Blackjack Splitting Pairs - Sixes: Split a pair of sixes playing against a dealer's visible 2 through 6. Otherwise, take the hit. A 2 through 6 is tough for the dealer because the busting chances are higher. Splitting the sixes produces two player hands that can't bust by taking one more card. Either or both will probably win when the dealer busts.

Blackjack Splitting Pairs - Sevens: Split a pair of sevens if the dealer shows 2 through 7. If the dealer has an 8 or better, take a hit. When the dealer shows 2 through 7, assuming a 10 in the hole, that's a hard total for the dealer of 12 through 17. Except for the 17, the dealer's hands are stiff, meaning they're more likely to bust on a hit. Split the 7s expecting a ten, and the player hand totals 17. This beats all the dealer's possible totals except 17, where the dealer has a good chance of busting anyway. When a dealer shows an 8, the total is likely 18, which beats the player anyway, so take the hit and hope for the best.

Blackjack Splitting Pairs - Nines: The strategy for playing a pair of nines is one of the few complicated approaches to splitting pairs in blackjack. Split nines when the dealer shows up cards of 2 – 6 and 8 – 9. Stand when the dealer up cards are 7, 10, Ace. A dealer hand with 2 - 6 is a stiff hand, which means a good chance of busting assuming a 10 on the hit. With a pair of nines, a player has a shot of getting two hard totals of 19, well within winning range. Given the preponderance of 10s in blackjack, a win is a reasonable expectation in this situation. When standing against dealer up cards of 8 or 9, the dealer total is likely 18 or 19. The only hope here is a push against an 18 and a loss against the 19, unless the player gets lucky on the split. With a ten or an ace up, the dealer probably wins, so there's no sense in losing any more money. With a hard 18 against a dealer 7, there's a reasonable chance of winning straight up without splitting, because too many bad things can happen when hitting on a nine.

So remember: Always split aces and eights, never split fives and 10s, and memorize the strategy for the rest. Then blackjack strategy will tilt the odds more in your favor.