This piece is meant to be used as a companion to the article Blackjack: Basic Strategy, where the basic technique of playing hard and soft hands was considered. It did not deal with the strategy of playing pairs, however. When you have two of the same card, you have the option of ‘splitting’, where you separate the cards and are dealt a new hand on each in addition. You must also place an extra bet on the second hand, and each one is played individually, allowing you to possibly win (or lose) two bets instead of just one.
Some pairs play exactly the same is every situation while others can vary depending on what card the dealer is showing. For example, a pair of aces or a pair of eights should always be split. This is because as individual cards when paired with tens, aces and eights are quite strong making 21 and 18 respectively. Additionally, hands of 12 (two aces) and 16 (two eights) are awkward and tend to bust frequently. On the opposite end of the spectrum is a hand of two tens, which you should always stand on. This is because 20 is already a very strong hand, and you will most likely end up with one or two weaker hands if you split it up.
Unfortunately, the rules outside of aces, eights, and tens get a little trickier. With almost all pairs, you split if the dealer has a two through six showing, and you stand if the dealer has a seven through ten showing. If you just do this, you are on your way to playing optimal blackjack, but there are a few caveats to remember. For one, a pair of fives plays exactly like a regular ten – double down if the dealer has anything besides a ten or an ace showing.
Secondly, if you are dealt two deuces, threes, or sevens for your starting hand, you should split when the dealer shows a seven in addition to the when he has a two, three, four, five, or six. When you have two nines showing, you should split on all cards except for a seven (where the dealer will have to stand on 17, losing to your 18), a ten (you are most likely going to lose to 20 anyway and it is better to lose only one bet instead of two), and an ace (same reason as 10).
The above rules cover all pairs except for the somewhat strange play of two fours, which give you a total of eight. From the earlier rules, you should remember that you always hit when you have an eight, regardless of what card the dealer is showing. With an eight, you are hoping to make an 18, which is a reasonably strong hand to play.
A pair of fours only plays differently if the dealer is showing a five or a six. This is because the dealer is most likely to bust on those cards (any card seven or higher will cause him to bust), and by splitting your fours, you give yourself two chances to win when if he busts. Hopefully you now understand the basics of splitting your cards at blackjack. If these rules are confusing, remember that you can ask the dealer for advice or purchase a strategy card at most casinos.