In Blackjack When Should You Split
- Image: pixabay Why you should surrender (and other blackjack tips) When it comes to blackjack strategy, the most important thing to remember is that the goal of the game is to beat the dealer.
- The first kind of total of 16 you should think about is a pair of 8s. You should always split a pair of 8s. The reasoning behind this should make sense. You’re trading a mediocre hand for 2 hands which are likely to improve. More cards in the deck will improve an 8 than will hurt it. Any ace, 10, or 9 will give you a better total than 16.
- In Blackjack When Can You Split Cards
- In Blackjack When Should You Split Peas
- In Blackjack When Should You Split End
If you’ve spent any time studying blackjack basic strategy, you’ve probably heard that you should always split aces and eights. The goal of this post is to explain why this is the appropriate move in almost any variation of blackjack. It doesn’t matter what the dealer’s face-up card is, by the way. Splitting aces and eights is always the right move.
A Note on “Basic Strategy”
If you’re new to blackjack, you might not have heard what basic strategy is. In brief, it’s a table of the mathematically correct moves to make in any blackjack situation.
You have 2 pieces of information, which are cross-referenced on a blackjack basic strategy chart:
When Should You Split Aces in Blackjack? When playing any Blackjack game you are going to get dealt out all manner of card combinations as your first two cards. When playing poker games an initial two card hand many players will be hoping are dealt out to them are a pair of Aces, and that hand combination can often be a very beneficial one for. If you have a total of 18 that’s made up of two 9s, you must decide whether to split your hand or not. Most of the time, you will split your hand, but there are exceptions. You’ll split a pair of 9s if the dealer has a 6 or less showing. You’ll also split 9s if the dealer has an 8 or 9.
- What’s in your hand
- Half of what’s in the dealer’s hand
In your hand, you have a soft total, a hard total, and possibly a pair of cards of the same rank.
In the dealer’s hand, you know one of his or her cards. In almost all blackjack variations, the dealer gets one card face-up.
The correct decision in any of these situations is the one with the highest mathematical expected return.
If you make the correct mathematical decision on every hand, you reduce the house edge that the casino has over you to its lowest possible number—usually between 0.5% and 1%, depending on the rules at the casino.
How Splitting Cards in Blackjack Works
One of the options you have in blackjack is “splitting” a pair of cards of the same rank. When you do this, you start 2 hands. The first card of each of those hands is one of the 2 cards from your original hand.
You also must put up another bet when you split your hand. You then play each hand independently of each other.
You could win both the new hands, lost both the new hands, or lose with one and win with the other.
Basic strategy tells you that you should never splits 4s, 5s, or 10s. It also tells you that you should always split aces or 8s.
Why You Do the Things You Do in Basic Strategy
Basic strategy has been derived by mathematicians and computer programs who run simulations of millions of hands. They look at the results of those hands to determine the playing decision which wins the most or loses the least amount of money in each situation.
In Blackjack When Can You Split Cards
But some of the thinking behind basic strategy makes sense, too.
Here’s an example:
You should never split 10s, no matter what the dealer’s upcard is.
Why not?
You have a hard total of 20. The only possible hand that could beat that 20 is a 21. It’s such a good hand that it’s hard to imagine improving your chances by creating 2 new hands—even though any hand which starts with a single 10 is going to turn out pretty good.
Let’s think about how many cards left in the deck will improve on a hard total of 20.
If you get a 10 on your new hand, that’s great. You now have what you would have had originally. You have 14 cards left in the deck which are worth 10 points. (There are 16 of those cards to begin with, but you already have 2 of them.)
If you get an ace, that’s even better. You get 3 to 2 on your payout. That’s not as likely as getting another 10, though. There are only 4 aces in the deck.
All the other cards, though, give you a worse hand. That’s a total of 32 cards which will give you a hand that’s not as good as your original hand. That’s about a 65% chance of getting a hand with a total not as good as you started with.
And some of those cards are rough, too. You get a 2, 3, 4, 5, or 6, and you have a stiff hand. That’s a hand that’s unlikely to beat the dealer unless you hit it. But it’s also a hand that has a good chance of going bust if you hit it.
This kind of thinking—about how good your total is, and about how the remaining cards in the deck might affect that total—is crucial to an understanding of basic strategy.
Let’s look at one more example:
You should also never split 5s. That’s a hard total of 10.
That’s a lousy total as it stands, but it’s a total you can’t bust with an additional card. Any card will improve your total, and a lot of those cards will give you a hand you’ll feel good about standing on. You have 16 cards worth 10 left in the deck, and 4 aces. That’s 20 cards that will give you a total of 20 or 21.
If you get a 7, 8, or 9, you also have a solid total you can feel good about. That’s another 12 cards, for a total of 32 cards which will improve your total.
Even if you get a 2, 3, 4, 5, or 6, it’s not the end of the world. You’re liable to get a stiff hand, but it’s not as likely as getting a good hand.
But what would happen if you split those 5s?
You’d wind up with 2 hands with a starting card of 5. It’s impossible to get a card on top of that to make you feel good about your hand. If you get an ace, you have a soft 16, and that’s probably the best you can hope for. If you get a 10, you have a total of 15, which is awful. It won’t beat the dealer, and it’s likely to bust when you take another card.
The other, lower value cards don’t help much either. A 9 gives you a total of 14, which is also awful. An 8 gives you a total of 13. Nothing to write home about there, either.
What Happens When You Split Aces
A hand of 2 aces that you don’t split is just a soft total of 12. That’s not terrible, because it’s hard to bust. But it’s not likely to win.
On the other hand, if you take a mediocre hand and turn it into 2 really good hands, you’ve accomplished something.
And let’s face it—anyone with a brain in his or her head knows that an ace is the best possible starting card in blackjack. If you get a 10 on top of that ace, you have a blackjack, which pays off at 3 to 2.
In fact, in a lot of casinos, you can split those aces and then immediately double down on them.
Remember, you have 16 cards worth 10 points each in the deck—more than any other specific total. Most of the cards aren’t worth 10 points, but enough of them are that you can be optimistic about getting that natural at least some of the time.
But if you miss your 10, you still wind up with a good hand almost every time. If you get a 9, you have a total of 20, which is a great hand. If you get an 8, you have a total of 19, which is good. Even a 7 leaves you with a total of 18.
If you get a 6 or less, you don’t have such a great hand. But because one of the cards is an ace, you’re going to be able to try to improve that hand with little fear that it’s going to bust.
What Happens When You Split Eights
First, if you have a hand made up of 2 eights, you have a hard total of 16. That’s a lousy hand. You’re probably going to stand rather than take an additional card. Either way, you’re unlikely to win. If you stand, the dealer will probably wind up with a better total than you. If you hit, you’re probably going to bust.
On the other hand, if you split this into 2 new hands, each with a starting card of 8, a lot of good things can happen.
16 of the cards in the deck are worth 10 points, so you have a reasonably good chance of getting a total of 18 on your new hand.
If you get a 9, you have a total of 17, which is also a big improvement.
If get another 8, which is unlikely, since you already have 2 of them, you’re no worse off than you were to begin with.
But What If the Dealer Has a 9 or 10 Upcard?
Thoughtful blackjack players might wonder why you would split 10s or 8s in the face of a dealer’s upcard of 9 or 10. After all, the odds are good that the dealer will beat you. Aren’t you just losing twice as much money by splitting in this situation?
The crucial factor to keep in mind is whether you’ll win more in the long run or lose more in the long run by making a specific decision. In the case of a dealer 9 or 10, you’re not trying to win more often. You’re just trying to lose less often.
This is built into the logic of the game and into the logic of basic strategy.
Here’s an example:
Any total of 12, 13, 14, 15, 16, or 17 is probably going to lose to the dealer—more than 51% of the time, anyway. And you’ll see one of those totals a little more than twice out of every 5 hands.
The best you can do in that situation is try to lose less often than you would if you made another decision.
Let’s say you face a dealer upcard of 9, 10, or ace with a pair of 8s. If splitting weren’t an option, the correct strategy would be to hit the hard total of 16. You’d lose $52 out of every $100 you bet in this situation. (It seems like you’d lose more often than that, even, but remember—the dealer doesn’t always have an ace in the hole.)
But if you split that into 2 hands that each start with an 8, you’ll lose $43 of every $100 you bet in this situation. Yes, you’ve put twice as much money into the situation. But each of those should be thought of as 2 bets with a better on-average outcome than the one bet with a terrible possible outcome.
These are both losing situations, but one situation saves you $9 on average per $100 bet.
In fact, you’ll sometimes get some grief from the other players or even the dealer when you make this decision. The best thing to do is ignore them. They mean well, but they clearly don’t understand the math behind the game or behind basic strategy.
As an aside, I used to employ a former blackjack dealer to clean my house. Her understanding of the game and the math behind it was abysmal. Don’t make the mistake of thinking that just because someone deals blackjack for a living means they understand how to minimize the house edge.
Always follow basic strategy, and always ignore other people who advise you to do something different.
Splitting Aces Is a No-Brainer, Though
Even people who are a little confused about basic strategy in blackjack understand the logic behind splitting aces. You’ll occasionally run into someone who’s too timid or too under-bankrolled to make the mathematically best choice. If you’re in a helpful mood, you might offer to cover the extra bet for that person at no risk to them. The dealer might or might not allow this. The player might or might not take you up on it.
But if he or she does, it’s a good deal, because you have an excellent chance of getting that 3 to 2 payout for a blackjack.
If you’re counting cards, you might even be in a situation where the deck is rich in 10s. In this case, such a play makes even more sense. That’s the reason card counting works, after all—it measures the ratio of 10s and aces in the deck to the number of lower cards in the deck.
Splitting and Re-Splitting Aces
It’s possible when you split aces to get another ace on top of one or both of your new hands. In that case, if the casino allows it, you should split again. You could easily wind up with 4 hands in play at a time, all of which stand an excellent chance of turning into a blackjack.
Not all casinos allow this, and it’s easy to see why. At many casinos, after you split aces, the casino only lets you take one additional card. If you were to get another ace and not have the option of re-splitting, the casino has you. A total of 12 versus almost any dealer total is a likely loser.
Luckily, that doesn’t come up often enough to worry about it. Just remember that you always split aces, regardless of the dealer’s upcard, and you’ll be fine.
Conclusion
And that’s my explanation of why you should always split aces and 8s when playing blackjack. The dealer’s upcard doesn’t matter in any situation. You’ll either win more money more often or lose less money in the long run.
Splitting aces is an aggressive move that increases your winnings dramatically. Splitting 8s is a defensive move that helps to minimize your long-term losses.
Both are the mathematically correct play.
Blackjack has many wonderful qualities. It’s a game where your decisions matter. It’s also a game where you can get an edge over the casino (if you know how to count cards).
Most of all, it’s just plain fun.
But blackjack is more fun when you’re winning more often.
Luckily, it’s a game where the mathematically correct way to play each hand has already been figured out. Computer programmers have run millions of hands of blackjack through simulators to come up with the moves that have the highest expected value.
A word about that:“Expected value” refers to how much a bet is worth. In some situations at the blackjack table, the expected value of a specific decision is positive. It might be more positive than other positive decisions.
In some other situations at the blackjack table, you must choose between the lesser of several evils. If you have a stiff hand, the best you can do is go with the decision that loses you the least amount of money in the long run.
As luck would have it, you only have a handful of totals to make decisions about. The highest possible total you can have without busting is 21. The lowest possible total with 2 cards is 4.
In the post below, I’ll look at each possible total and how it could occur. Then I’ll explain how to play that total based on which cards it’s made of and what the dealer has as her face-up card.
All these explanations are based on basic strategy.
A Total of 21
When you have a total of 21, you should always stand. It doesn’t matter what cards make up that total. It doesn’t matter what the dealer’s up-card is.
You always stand with 21. Any other choice costs money.
A Total of 20
You’ll always stand with a total of 20, too, no matter what the cards are. It also doesn’t matter what the dealer’s face-up card is.
The reasoning behind this is clear. There’s only one possible total the dealer could have which will beat a 20, which means you’ll win with it most of the time.
You might need to decide whether to split a hard total of 20. If you have 2 cards of the same rank, you can put up another bet and start 2 hands using the cards in your hand as the first card of the 2 subsequent hands.
It seems like this might not be a bad idea. After all, any hand with a 10 as its first card is probably going to turn out okay.
It’s a mistake, though. Most of the time, you’ll wind up with 2 hands that aren’t as strong as your total of 20. There are more cards in the deck that aren’t worth 10 or 11 than there are cards which are worth 10 or 11.
A Total of 19
You will ALMOST always stand on a total of 19, regardless of which cards make up the total.
But there’s one exception:
If you have a soft total of 19—an ace and an 8—you’ll double down. But only if the dealer has a 6 showing.
In some casinos, you’re not allowed to double down on a soft total of 19. If that’s the case, you’ll just stand.
On any other total of 19, though, you’ll stand. It’s such a strong hand that it will beat anything except a total of 20 or 21 from the dealer.
But even if you suspect that the dealer has one of those totals, your odds of winding up with a worse hand are too good for it to be a smart move to take another card.
The only reason you double down against a dealer’s face-up 6 is because the dealer is so likely to bust that it’s worth the risk.
A Total of 18
If you have a total of 18 that’s made up of two 9s, you must decide whether to split your hand or not. Most of the time, you will split your hand, but there are exceptions.
You’ll split a pair of 9s if the dealer has a 6 or less showing. You’ll also split 9s if the dealer has an 8 or 9.
If the dealer has a 7, 10, or ace showing, you’ll stand.
If you have a total of 18 that includes an ace that can be counted as 1 or 11, you have a “soft” 18. If the dealer has a 6 or lower showing, and if the casino allows it, you’ll double down on this hand.
If the casino doesn’t allow you to double down on a soft 18, you’ll stand instead.
If the dealer has a 7 or 8, you’ll stand on a soft 18.
If the dealer has a 9, 10, or ace showing, you’ll hit a soft 18.
Being able to count the ace as 1 or as 11 gives you some flexibility with how you play this hand. The combination of the possibility to improve your hand and the possibility that the dealer will bust results in the possible doubling down decisions.
Any other total of 18 will be a hard total, and you’ll always stand on a hard total of 18.
A Total of 17
If you have an ace that counts as 1 or 11, you have a soft total of 17. In that case, you should double down if the dealer has a 3, 4, 5, or 6 showing. If the dealer has any other card showing, you should hit this total.
If you don’t have an ace, or if counting the ace as an 11 would bust you, you have a hard total of 17. It’s easy what to decide to do with a hard 17:
Always stand.
A Total of 16
Once you get down to the total of 16 or less, you’re getting into “stiff hand” territory. A stiff hand is one which is likely to bust.
It doesn’t matter, though.
There’s still only one correct way to play each stiff hand, too.
The first kind of total of 16 you should think about is a pair of 8s. You should always split a pair of 8s. The reasoning behind this should make sense. You’re trading a mediocre hand for 2 hands which are likely to improve. More cards in the deck will improve an 8 than will hurt it. Any ace, 10, or 9 will give you a better total than 16. (And there are 16 cards worth 10 in the deck, so that’s almost half the deck in total.)
The second kind of total of 16 to worry about is a soft 16. Again, this is a total where the ace can count as 1 or 11. You will NEVER stand on a soft 16.
You’ll double down on a soft 16 if the dealer has a 4, 5, or 6 showing. If the dealer has any other card showing, you’ll fold.
Finally, you need to know what to do with any other hard total of 16. You’ll stand if the dealer has a 6 or less showing. You’ll hit if the dealer has a 7 or higher showing.
If the dealer has a 6 or less showing, you’re hoping she’ll bust. Otherwise, you’re hoping to improve your hand so that you have a fighting chance.
A Total of 15
A soft total of 15 is easy to play. You’ll play it just like you would a soft total of 16, in fact. You’ll double down if the dealer has a 4, 5, or 6 showing. Otherwise, you’ll hit.
A hard total of 15 isn’t hard to play, either, although it’s a bummer of a hand. Again, you’ll play a hard 15 just like you would a hard 16. Hit if the dealer has a 7 or higher. Otherwise stand.
A Total of 14
If you have a pair of 7s, you need to decide whether to split. You will split if the dealer has a 7 or lower showing. If you don’t split, you’ll treat the hand as any other hard 14.
If you have a soft 14, you will never stand. You’ll double down if the dealer has a 5 or 6 showing. Otherwise, you’ll hit.
If you have a hard 14, you’ll play it just like a hard 15 or 16. Stand if the dealer has a 6 or less showing. Hit if the dealer has a 7 or higher showing.
A Total of 13
A soft total of 13 is played just like a soft 14. You’ll double down if the dealer has a 5 or 6. Otherwise, you’ll hit.
A hard total of 13 is played just like a hard 14, 15, or 16. Stand if the dealer has a 6 or less. Otherwise, hit.
A Total of 12
The first kind of 12 total to worry about is a pair of 6s. (You always consider whether to split first.) You should double down if the dealer has a 6 or lower showing. If not, you’ll treat the hand just like you would any other hard total of 12.
Next, you’ll think about a soft total of 12. This could mean you have a pair of aces. In that case, you always split. (Just remember—always split aces and 8s.)
There’s no other way to get a soft total of 12, so you’re left with the possibility of a hard 12. If that’s what you have, you stand against a dealer 4, 5, or 6. Otherwise, you hit.
A Total of 11
If you have an ace and a 10, you COULD consider that a soft total of 11. But really, you have a blackjack. Just accept your winning with grace.
In Blackjack When Should You Split Peas
On any other total of 11, you’ll double down. That’s an easy decision, because you have lots of cards which will increase your total to 21. There’s no real downside to doubling down on an 11, because it’s impossible to bust such a hand.
A Total of 10
You never split 5s. They’re always treated as a hard total of 10.
If you have a soft total of 10, you really have a soft total of 20, and I’ve already covered that. (Think about it.)
With a hard 10, which is really the only way you’ll ever have a total of 10, you’ll almost always double down. The only time you won’t double down is if the dealer has an ace or 10 showing. In that case, you’ll just stand. (You don’t want to put extra money into play because of the increased likelihood that the dealer will have a 21.)
A Total of 9
A hard 9 is played ALMOST exactly like a hard 10. You should double down if the dealer has a 3, 4, 5, or 6. Otherwise, hit.
A Total of 8
You never split a pair of 4s. (In fact, you can remember this rule—never spit 4s, 5s, or 10s.)
In fact, there’s only ONE way to correctly play a hard total of 8. Always hit.
A Total of 7
Always hit a hard total of 7.
A Total of 6
If you have a pair of 3s, split if the dealer has a 7 or lower showing. Otherwise, just hit.
If you have any other hard total of 6, just hit the hand.
A Total of 5
Always hit a hard total of 5.
A Total of 4
If you have a pair of deuces, play it just like a pair of 3s. Split if the dealer has a 7 or lower showing. Otherwise, just hit.
Conclusion
That’s it.
You only have 18 possible starting totals in blackjack. Once you’ve learned how to play each of those totals correctly, you’ve mastered basic strategy.
Why is that a good thing to do?
If you’ve mastered basic strategy, the house edge for most blackjack games is between 0.5% and 1%, making it one of the best games in the casino.
If you misplay these hands, the house edge goes up. Most players are bad at basic strategy, by the way. If you look at the casino’s numbers, the average blackjack player is so bad that he’s facing a house edge of between 4% and 5%.
With those kinds of numbers, you might as well play craps or roulette. You don’t have to make any playing decisions with those games.
memorize basic strategy in this way.