Knowing when to split in blackjack is one of the least understood parts of the game, even among experienced players.  

Splitting pairs isn’t as exciting as doubling down, but it’s still a good opportunity to tilt the odds in our favour and beat the dealer at their own game. 

Luckily, it only takes a minute to learn when to split in blackjack!

What does split mean in blackjack?

When you play blackjack online or in a live casino, you’re dealt 2 cards face up. If you get dealt a pair – that’s 2 cards of the same value like 22 or KJ – blackjack rules give you the option to split them, for the cost of an extra bet. 

Your cards now each become the first card of 2 new hands. And as everyone knows, 2 hands are better than 1! Just make sure you play ‘em well. 

Here’s what happened when you are dealt a pair of eights. We pay an extra bet to split the pair, and the dealer literally splits them up, creating 2 separate hands. 


Why would you split a pair?

Every rule in blackjack is there to help either the player or the house, and a good blackjack game will have a balance of both.  

You can learn more on that in our Blackjack guide. Splitting is part of the player’s toolkit and it helps reduce the house edge by up to 0.40%.  

There are 2 types of situation where splitting helps you out. 

  • The defensive play: Break up a pair with a bad total value into 2 cards with better scoring potential (e.g. a pair of 8s) 
  • The attacking play: Split a pair in order to get more money on the table against a weak dealer hand ( a pair of 4s versus dealer’s 6)

Splitting rules

At any online blackjack table at PlayOJO, you will be allowed to split any 2 cards of the same value, and it will cost you the same amount as your original bet. 

The splitting rules will normally allow you to split up to 3 times for a maximum of 4 hands, and you can double after any split card, known as the DAS rule.

blackjack splitting rules chart

When splitting Aces, you only get only 1 more card to for each Ace. If that card’s a 10, the hand is worth 21. It does not count as Blackjack. Likewise, if you split Tens (nooooooo, don’t do it!), any Ace you get will not give you Blackjack. 

Top 3 pairs to split in blackjack

Misplaying blackjack splits might only cost you less than half a percent of your RTP, but that all adds up over time. Memorize these popular plays and you’ll instantly play better when you play blackjack for real money online.


split 8 on blackjack table

Your hand is worth 16, as bad as it gets. It’s obvious why you’d want to swop 16 for a couple of 8s against a dealer’s 6, for example. But against an Ace, it may seem crazy to get more chips in the middle. But the numbers tell us you’re better off in the long run even against an Ace. 


split aces on blackjack table

When you get a pair of Sure, you only get 1 more card on each Ace and Tens won’t count as Blackjack. But right now your Aces are worth 2 or 12! Split ‘em and you’ve got two hands already worth 11. It’s the best possible up-card and it’s likely to get a lot better. 


split 9 on blackjack table

You should split a pair of Nines against anything except a 7, 10 or Ace. Your 18 is in great shape against a 7. Against a 10 or Ace, it’s best to stand and take your medicine. Against all other dealer cards, splitting Nines is the smart play as your 18 becomes two possible 19s. 

Pairs you should never split in blackjack

We’ve shown you when to split in blackjack, but it’s just as important to show you when NOT to split, too! Splitting these pairs is a cardinal sin and will cost you dearly in the long run.   


split 10 on blackjack table

Some players get excited when they see a bad dealer card, but it’s a criminal play to give up a hand worth 20 that is is a very strong position to win. The only exception to this rule is if you are card counting, as you may sometimes know when there are more Tens and Aces in the deck.  

Fours or Fives 

split 5 on a blackjack table

You’re breaking a good hand worth 8 or 10 to create hands that will probably end up closer to the deadly 16. Even if the dealer has a 6, don’t get tempted! It’s far better to double down instead. 

Strategy chart for splitting

If you want to know exactly when to split or not to split in every possible scenario, a basic blackjack strategy chart is the place to go.  

As we’ve already covered, splitting Aces and Eights are almost always good moves. But as you can see from this strategy chart for an 8 Deck S17 game, there are many more opportunities to split.

Display the PAIRS section of a BJ Basic Strategy Chart for 8 Deck S17 with the chart title Split Strategy Chart for 8 Deck S17

If you play blackjack regularly, it’s worth learning all of the split rules in this chart. Casinos love it when players don’t learn how to play blackjack perfectly or if they simply go off-piste sometimes, because every time you deviate from the correct split strategy, you are giving up a tiny advantage and increasing the house edge.

Most asked questions

Can the dealer split? 

No, the dealer plays to a very limited set of playing rules. Depending on the value of their hand, they can only hit or stand. The dealer can never double or split, so when they deal themselves 9-9 or 10-10, they will stand. For all other pairs, they will hit.  

What is the best pair to split in blackjack? 

How much money a split pair makes you depends on what the dealer has. But in general, even though you only get 1 more card, Aces are the best pair to split, as you start each new hand with 11 – the best possible starting value in blackjack.  

Congrats, you’ve learned how to split in Blackjack!

So that’s blackjack splitting in a nutshell. Now you’re a pro, it’s time to go. Good luck.

Daniel Grant

Daniel Grant

Dan Grant has been writing about gambling for 15 years, and been fascinated by beating the odds for even longer. Now he’s on a mission to help others bet smarter and avoid the mistakes he made. When he’s not obsessing over bankroll strategy or counting cards badly, he’s hosting The OJO Show podcast.