Lesson 16 – The Advanced Course – Part 4

This free course on blackjack and card counting was created by the GameMaster, publisher of the GameMaster Online website. It is reproduced here in its entirety with permission of the author. His 24-lesson course is an excellent introduction to winning blackjack.

To start at the beginning, visit the Welcome page.

Basic Strategy Variations: To Split or Not To Split

The primary factor to consider when splitting pairs is whether or not your casino of choice allows doubling after splitting (DAS). If DAS is allowed, you must have the proper basic strategy memorized. I see players make a lot of errors in splitting pairs, primarily with a hand of 8, 8. Most know that a pair of 8s should be split against all up cards, but most stand when they hold them against a dealer’s 10. The cost of that mistake isn’t huge, simply because a hand of 8,8 is fairly rare. But by standing, a player has an expectation of -.537% and by splitting (if DAS is allowed), an expectation of -.483% is realized. So, the extra money which is put to risk does — in the long run — give a better return. Think of it this way. Would you rather stand with a 16 against a 10 or hit an 8 against a 10? By splitting, you get to hit an 8. Incidentally, the numbers also indicate that splitting is best when DAS isn’t allowed, though there isn’t as big a difference.

As the true count goes up, you’ll split more and as it goes down, you’ll split less. One play which is justified by a high count is the splitting of 10s. For example, there may come a time when it’s worthwhile to split a pair of face cards against a 6. I counsel my students to avoid that play since it draws such a negative reaction from other players at the table. I don’t really care what the others at a table think of my play, but if the floor personnel are alerted to what I’ve done, their initial suspicion may be that I’m a counter. If they’ve seen me playing good basic strategy and suddenly I have a big bet out and I do something like splitting 10s against a 6, they’re going to think I’m either very stupid or very smart. I guess it all relates to the image your projecting in the casino; if it’s one of a ‘wild man’, then go for it. But if you’re quiet, polite and a non-drinker, I’d advise against making the play.

All other splitting situations should be followed to the letter; especially that of splitting 4s against a 5 or 6 (if DAS is allowed). Most people don’t have the pairs part of basic strategy memorized perfectly, so they won’t know what’s right or wrong when you do it and most think it’s wrong to split 4s. Nothing quite like making the right play and looking like a dummy when you do it!

As you go through the numbers on splitting pairs, you’ll see that some don’t agree with those published by Stanford Wong and other authors. As I’ve explained before, some have been modified as a result of Friedman’s study on risk-averse play, and I feel they take no advantage from you yet do lower your risk somewhat.

Note from the BlackjackInfo.com editor:

There are slight differences in the GameMaster’s index numbers published here and the optimized numbers on the
BlackjackInfo Advanced Blackjack Strategy Cards.

These differences are usually due to the use of risk-averse calculations by the GameMaster. I maintain that for the majority
of players (who are not playing near the maximum Kelly fraction of their bankroll), straight indexes are preferable to
risk-adjusted ones. In any case where risk-averse indexes differ from straight indexes, even by several points,
the decisions are quite close and the effect of choosing one index style over another is minimal.

Basic Strategy Variations:
Double after split allowed.
3,3 vs. 2 Hit at 0 or lower. (Instead of splitting.)
4,4 vs. 5 Hit at -1 or lower. (Instead of splitting.)
4,4 vs. 6 Hit at -2 or lower. (Instead of splitting.)
6,6 vs. 2 Hit at -1 or lower. (Instead of splitting.)
8,8 vs. 10 Stand at 8. (If the count is really high, you do stand instead of hit.)
9,9 vs. 7 Split at 6. This is a “risk-averse” play.
← Previous:

33 comments on “Lesson 16 – The Advanced Course – Part 4

  • stefan said:

    hi ken !!! these choices are the same also for european blackjack ? in very bad- low counts a hand like pair of 6 against a 4 or a 5 dealers how should be played ? hit stop or split ?knowing the remaining cards it plays a little with your mind and the bs .thanks 4 your answer

    • No-hole-card rules only change anything when the dealer has a ten or an Ace up. Therefore all strategies and index numbers other than against the dealer ten and dealer Ace are identical in the US game and the European game.

      I don’t have index numbers for not splitting sixes against a 4 or 5. They would likely be worse than -10. In the event you did reach such an index, you would hit instead of split. In general, remember that strategy variation is far less important than bet variation, and you can easily do more damage than good by deviating from basic strategy when you aren’t sure of the appropriate index. If you don’t know the index for sure, just play basic strategy, no matter what you think you know about the deck composition. Index numbers are complicated, and deviating when you shouldn’t is expensive.

  • terry said:

    hi admin!!when should we buy insurance?thank you so much~~

    • Buy insurance at a true count of +3. (+2 in single deck.)
      Split TTv5 at +5. Split TTv6 at +4. However, ten splits probably aren’t worth the extra attention they draw for most players.

      • terry replied:

        thank you very much!you are so kind!Do you mean split ttv6 is not worth even at a true count of 10?

        besides, can you tell me when should we surrender while 17vs10 and 18vs10,A5vs10,A6VS10,A7VS10?thank you!!!!

        • terry replied:

          hi Ken Smith!when we are at a true count of +10,we should play one bet or several bets in one game?thank you so much~~~~~

        • Whether it’s worth splitting tens or not really depends on where you are playing, and how likely you are to have trouble because of it. If it causes you to get backed off, it’s certainly not worth it, no matter the count.

          I don’t have surrender index numbers handy at the moment, so I’m no help on the latter question.

          You also ask in another comment about whether you should play one hand or multiple hands at TC+10. Spreading to multiple hands has lots of benefits, so if you can, it’s probably a good thing. You don’t need a rare true count of +10 to do it either. 🙂

          • terry replied:

            thank you so much!but what is the meaning of “If it causes you to get backed off”,can you explain it?thank you^^

            • “Backed off” means you get the tap on your shoulder, and are told you can play other games, but are no longer allowed to play blackjack. If you are playing the game with an advantage, you can count on this happening sometime in your career, probably pretty early. It’s a cat and mouse game.

  • terry said:

    when should we split 10.10?and when should we surrender while 17 against dealer’s hand 10?thanks a lot!!!

    • No peek means that the dealer does not check for blackjack before the players complete their hands. It also applies in games where the dealer does not take a second card until all players are done. The reason it affects the strategy is because in the typical US-style peek game, players know for sure that dealer does not have a blackjack before making a decision to split or double down. In a no-peek game those moves are riskier against a dealer ten or ace, because you may lose all of the bets to a dealer blackjack.

  • In the European and UK game, where dealer has no peek at his hole card, if the player has A,A v A and splits, then obtaining 2 x 21’s, the dealer gets a natural and wins all the splits. It is for this reason that a very experienced pro said A,A is not a split. However, another source says to split anyway since the split A’s are strong enough to warrant it.
    The vast majority of books on BJ are not written with enough consideration for European/UK rules.
    What do you suggest please?

    • Against the UK no-hole-card game, do not put more money on the tables against a dealer ten or Ace, with one exception. Still split Aces against a dealer ten. My Strategy Engine with the “No Peek” setting will show you the correct strategy.

  • On a flat shoe and European game, DAS, 4,4 v 5 (6) is a split. I hate this move and I split. From my probability charts a 4 v 6 less chance of winning than 8 v 6. So why is the BS move to split?

    • It’s often difficult to show a specific reason for the basic strategy of a particular hand. In this case, you’ll just win very slightly more by splitting (and making any possible resplits or double downs), than if you just hit the 44v6 hand. You really can’t just use probability of win charts unless you take into account all the downstream possibilities, and also the percentage chance of a push on any of the multiple hands. It’s complicated to figure manually, which is why combinatorial analysis software is used to determine the optimal strategy.

  • Hi Ken

    Gr8 site and delivery. Thank you.

    I have 3 questions regarding splits. The 8,8 v 10; 4,4 v 5 (6); and A, A vAce

    I recently had a shoe that went to TC5+ and had max bets over 2 boxes. The first box produced a split and double. Which in turn produced another double. The second box produced a split and double also. The count had now come down to TC3+. The split was 8.8 and dealer was 10. Would u believe it, the split produced 2 more spits each being 8,8. I split one more time and decided I had too much money on the table and just stuck the final 8,8. My sessional roll just about contained all these splits and doubles but my nerves ran out as I decided it was too much. Should the correct play be to keep splitting 8,8s v 10 so long as sessional bank could contain it? This is UK rules.

    • First, 88vT in UK rules is not a split, because of the risk that a dealer blackjack could wipe out all your multiple bets.

      But I’ll answer your real question assuming that the circumstance at hand is an appropriate split…
      Mathematically yes, you should continue to split as long as that is the correct strategy. But it is not unreasonable to decide at some point that the risk is too high. If you are concerned about the session bankroll, it is not terribly expensive to decide to limit your exposure on a single hand. In my opinion, you should always be willing to put at least four bets at risk on a hand. If you’re not comfortable with that, your bankroll is not big enough. But beyond four bets, use your discretion.

  • Lionel said:

    For 8,8Vs10, do you stand at 8 and higher or is it specifically just at 8?
    Also, for 9,9Vs7, do you split at 6 and higher or is it specifically just at 6?

    • I don’t know why the GameMaster did not explicitly state “or higher” on those indexes.
      Yes, 88vT stand at +8 or higher, and 99v7 split at +6 or higher.

  • For these charts on whether to hit, split , double , or stand is the determining count the true count or running count

  • dave said:

    thanks for your help this is a great site well done for making it

  • Dave said:

    shouldnt you surrender 8,8 against a 10 if the count is high rather than stand as if not splitting you just play it like a normal 16?

    • Yes, in that situation, surrender is best.
      Let me explain for other readers: 88vT is a split in basic strategy, but once the true count reaches +4, you should no longer split, but instead play the hand as 16.
      If surrender is possible, do it. If not, stand (because the count is 0 or more, which is the index for 16vT.)

      Notice that the +4 index for the 88vT play is exactly the opposite of most split index numbers, since you split on low counts but not in high counts.
      This kind of “reverse” index only happens with a handful of decisions. Because they can be so confusing, I did not include any reverse indexes on my advanced strategy cards.

  • mike said:

    Whats the veriation for dealer must hit soft 17? I would lile that chart if possible. Thanx

  • Ben Nelson said:

    Thanks for answering my last question; I think this is the best spot for my question about doubles and splits.
    A few casinos offer to “pay for your doubles and splits.”
    I’m guessing this is actually very few hands, but how does this affect a player advantage (assuming you keep using correct strategy)?
    Thanks again,

Load More Comments

Leave a Reply

Advanced Formatting?

If you are familiar with HTML, you can use these tags and attributes in your comment:

<a href="" title=""> <abbr title=""> <acronym title=""> <b> <blockquote cite=""> <cite> <code> <del datetime=""> <em> <i> <q cite=""> <s> <strike> <strong>


A valid URL is required.