Blackjack Why Always Split 8s

3/30/2022 admin

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”

I just had my max bet out on a s17, 6d game playing 2 hands. Got 8s on the first, 18 on the second, dealer showed 10. Running count of 17 by the time i had to choose what to do, with about 1.5-2 decks left. Horrible, gut wrenching feeling. I split them and got 18 and 17 and the dealer pulled a 9 to beat all 3 of my hands.

To clarify further, you will always split 8s except in two rule sets: Double-deck, hit soft 17: Surrender vs A if allowed, else split Any decks, European no-hole card rule: Hit vs 10 or A (or presumably surrender if offered, although this is rare on these games). With 8s, mathematical analysis shows that splitting them loses less often over the long run than any Still a tough hand though. In most versions of Blackjack, when you are dealt a pair (two of the same card), you have the option to split them into two new hands. You must match your bet on the new hand, effectively doubling the amount wagered.

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:

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.

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.

One of the best rules in blackjack is the 3 to 2 payout when you get an ace and a ten on your initial hand. This is called a “natural” or a “blackjack”. But you’ll find more casinos than everoffering games where the payout for this hand is only 6 to 5.

Here’s how that works:

In a normal blackjack game, you bet $100. You get a natural. Your payout is $150.

In a 6/5 blackjack, you bet $100. You get a natural. Your payout is only $120.

Casinos offer other rule changes that favor the player in exchange for the reduced payout, but these rules are never good enough to account for that lower payoff on a natural.

Here are some examples of those favorable rules:

Single deck game
Dealer stands on soft 17
Player can double after splitting
Player can double on any 2 cards

These rule changes do have an effect on the house edge. A single deck game has a house edge 0.61% better than a single deck game. The dealer standing on soft 17 instead of hitting has a houseedge of 0.2% better. Being able to double after splitting is good for almost 0.15%. Being able to double on any two cards is worth about 0.2%, too.

In fact, if you combine all the rules variations I listed, you’ll get a net gain of 1.2%, which is significant.

Here’s the problem, though:

6/5 blackjack gives the house an extra 1.35% edge.

And most casinos don’t give you ALL the good rules. They just give you enough good rules to convince you to try their 6/5 game.