Blackjack is a popular casino game that pits players against the dealer in a contest to see who can get closest to 21 without going over. Players are dealt two cards face up, while the dealer gets one card face up and one card face down. There are several decisions players need to make during each hand, with the most common being whether to “hit” and take another card or “stand” and hold their total. One of the intermediate decisions is whether to “split” a starting hand. When dealt a pair, players have the option to split the two cards into separate hands, doubling their bet in the process. Each split card is then played out as its own hand according to normal blackjack rules. While some splits like aces and eights are no-brainers, the decision becomes more nuanced when holding a pair of 6s. In that case, the player must consider the dealer’s upcard before deciding whether splitting is the optimal move.
When to Split 6s
Splitting 6s can be advantageous or disadvantageous depending on the dealer’s upcard. As a general rule of thumb against most dealer upcards between 2 and 6, you should split your 6s. The reason splitting is favorable in these situations is it transforms a hand with an unfavorable 12 points into two hands that have more potential. Starting hands of 6-6 have a very low chance of winning at just 12 percent. By splitting, you are giving yourself two chances to improve. However, there is one major exception to this guideline: you should NOT split 6s if the dealer is showing a 3 as their upcard.
Why You Shouldn’t Split Against a 3
Splitting 6s when the dealer has a 3 showing is ill-advised for a couple reasons:
- The dealer has a very good chance of busting when showing a 3. Their odds of busting are about 42 percent, much higher than any other upcard. This makes a player total of 12 very competitive, since the dealer will likely bust.
- Splitting 6s produces two weak hands of 6 that are unlikely to improve. Hands of hard 6 have only about a 31 percent chance of winning. You are transforming one decent hand into two very weak hands.
- You are doubling your bet for little added benefit. In fact, you are reducing your chances of winning the hand by splitting.
So in summary, splitting 6s against a dealer 3 transforms a favorable situation into an unfavorable one. Stand with your 12 and hope the dealer busts.
When to Split 6s
As mentioned previously, you SHOULD split 6s when the dealer is showing a 2, 4, 5, or 6 as their upcard. Let’s examine each of these situations:
Dealer Upcard 2
When the dealer is showing a weak 2, they have only about a 35 percent chance of busting. Your 12 is no longer a great hand. By splitting, you are taking a hand you will likely lose and creating two hands that have decent odds. Hands of hard 6 win about 31 percent of the time against a 2. You are going from about a 35 percent chance of losing to two 31 percent chances of winning, which is a smart play.
Dealer Upcard 4
Against a 4, the dealer only busts around 27 percent of the time, so your 12 is not in a great spot. By splitting, you create two hands of 6 that will win 31 percent each, greatly improving your odds.
Dealer Upcard 5
A dealer showing a 5 busts around 23 percent of the time. Splitting your 6s produces two hands that win nearly one-third of the time each, which is preferable to holding your 12.
Dealer Upcard 6
When the dealer is showing a 6, their odds of busting are only around 21 percent, so your 12 is not likely to win. By splitting, you are exchanging a hand you will probably lose for two hands that win 31 percent of the time, which is the proper play.
Splitting 6s in Other Situations
We’ve covered that you should split 6s against all dealer upcards 2 through 6 except for 3. But there are a few other table situations that warrant discussion:
Dealer Upcard 7, 8, 9, 10
If the dealer is showing a 7 or higher, do NOT split your 6s. In these cases the dealer has at best a 17 percent chance of busting, so your 12 has very good odds of winning. Splitting would be exchanging that for two losing hands and doubling your bet, which is inadvisable.
Dealer Upcard Ace
Against an ace, most experts recommend surrendering your hand if that option is available, as the dealer has good odds of making a strong blackjack hand. If surrender is unavailable, do not split your 6s – stand and hope the dealer does not make blackjack. Splitting only produces two weak hands that will almost certainly lose.
Pair of 6s After Splitting
If you split a pair of 6s and are dealt another 6 on one or both hands, the rules vary by casino. Sometimes you can re-split up to 2 or 3 times. Other times you can only split once. If allowed, it is advisable to split each new 6 as it again improves your odds substantially.
Conclusion
To summarize the guidance on splitting 6s:
- Split against all dealer upcards 2 through 6 EXCEPT for a 3.
- Do not split against a dealer 7 or higher.
- Consider surrendering against an ace if available, otherwise stand.
- Re-split any subsequent 6s if the rules allow.
Splitting 6s when appropriate transforms a likely losing hand into two potential winning hands. However, exercise caution against a dealer 3, as standing with 12 is often the superior play in that case. Understanding when to split 6s versus when to stand will give you a definitive boost to your blackjack strategy and bottom line.
Splitting 6s Win Rate Data
Below is a table showing the win percentage when splitting 6s versus standing based on various dealer upcards, illustrating why splitting is advantageous in most but not all situations:
| Dealer Upcard | Win % if Stand | Win % if Split |
|---|---|---|
| 2 | 35% | 62% |
| 3 | 42% | 31% |
| 4 | 27% | 62% |
| 5 | 23% | 62% |
| 6 | 21% | 62% |
| 7 | 17% | 31% |
| 8 | 13% | 31% |
| 9 | 12% | 31% |
| 10 | 11% | 31% |
| Ace | 8% | 12% |
Other Splitting Decisions
While this article has focused on splitting 6s specifically, there are some other common splitting situations in blackjack:
Always Split
- Aces
- 8s
Splitting aces and 8s is advantageous in almost any scenario. Aces give you the opportunity to make blackjack, while 8s create strong starting hands.
Sometimes Split
- 2s
- 3s
- 7s
Whether to split 2s, 3s, and 7s depends greatly on the dealer’s upcard. Basic strategy guides can advise you when to split these.
Never Split
- 4s
- 5s
- 10s
Splitting 4s, 5s, and 10s is almost never a good play. You are transforming a decent hand into two weak ones, and surrendering several 4, 5, and 10 cards that could help form strong hands.
Using Basic Strategy
Memorizing split rules for every scenario can be overwhelming. For optimal blackjack play, utilize a basic strategy guide that will tell you exactly when to split any pair based on the dealer’s upcard. Basic strategy combined with card counting can give you the best odds against the house.
Some key tips:
- Make splitting decisions based on basic strategy, not gut instinct or superstition.
- Split conservatively as the dealer’s card gets higher.
- Be aware of the specific rules of the table, like re-splitting and double after splitting.
- Card count to gain added insight on when splitting is favorable.
Mastering split decisions takes practice but is a crucial skill to beating blackjack over the long run.