Doubling Down in Blackjack
Using Doubling to Increase Your Odds
Doubling down at the blackjack table is when you place another bet equal to your first wager after you receive your first two cards. You then receive a single additional card.
Here’s an example. You start a hand by placing a $25 bet. If your first two cards are a 9 and a 2, you slide another $25 bet forward and the dealer gives you one additional card. If you win the hand the dealer pays you even money on both wagers. In the event you lose the hand the dealer takes both of your bets.
The ability to double down on certain hands when you have a profitable situation is one of the things that makes blackjack an attractive game.
Once you determine which hands produce a long term profit you get as much money on the table as possible. You have to maximize your profitable plays to help cover all of the situations where you lose in the long run.
The good news is the most profitable plays have already been determined.
Learn the different rules and variations you might find and more about the specific situations where you need to double down.
Rules and Variations
Different blackjack tables have different rules concerning doubling. I’ve included each of the common rules, but always check before playing.
Player can double on any two cards: This rule is the most favorable to the player, opening up the possibility of doubling some soft hands (hands including an ace) that can’t be doubled using other rules.
Player can double any 9, 10, or 11: This covers all of the hard hands (hands that don’t include an ace) you want to double with, but it eliminates a few soft hands.
Player can double only on 10 or 11: At this point the house is starting to cut into your potential profit in a big way.
Player can’t double: The rarest of the rules variations, this one eliminates a large group of potential plays. If your table doesn’t allow splitting see if any other tables in the casino do.
Player can double after split: This rule is also favorable to the player, allowing the opportunity to get multiple wagers out in favorable situations. Using this rule you can get four or more bets out in some situations.
The only hard hands you need to consider doubling down on are 9, 10, and 11.
With any 11 you double down against every dealer card except an ace if the dealer stands on soft 17. If the dealer hits on soft 17 you double on every hard 11.
When you have a hard ten total, double against any dealer card except an ace or ten valued card. This is the same for both when the dealer hits or stands on a soft 17.
With a hard 9 double against any dealer 3, 4, 5, and 6.
Your soft hands create a different set of hands to double.
Soft 13 and 14 double against dealer 5 or 6.
Soft 15 and 16 double against dealer 4, 5, and 6
Soft 17 and 18 double against dealer 3, 4, 5, and 6.
If the dealer hits a soft 17 you also double with a soft 18 against a dealer 2 and a soft 19 against a dealer 6.
This may seem like a lot of hands to remember, but it shouldn’t take too long to learn them.
Start by deciding to only play dealer hits on soft 17 or stands on soft 17 tables. That way you only need to memorize one variation to start. You don’t have to worry about most other variations because you’ll double if allowed on all tables.
Here’s an example. If you plan to play on tables where the dealer hits a soft 17 follow this plan to help remember what to do.
It’s fairly easy to remember no hard hands except 9, 10, and 11 should be doubled, so let’s start there. Add another rule by doubling all hard 11’s and all 10’s except against 10’s and aces.
The dealer up cards of 3, 4, 5, and 6 are weak and cover three different situations. As you double a hard 9, soft 17 and soft 18 against all four weak cards, it’s the next rule to learn.
This only leaves soft 15 and 16 and soft 13 and 14. I try to visualize moving down a ladder from soft 17 and 18 to soft 15 and 16. As I move down the ladder one dealer card goes away. Moving down one more rung and another card goes away.
Don’t try memorizing all of the steps at once. Focus on the first few. Once you have them down add a couple more. It helps to play while you’re learning as it will start ingraining it in your memory faster than just trying to memorize them.
One last trick I have used is record the instructions and listen to them on a loop as I do something else. It’s the same way I used to memorize songs.
Doubling for Counters
If you count cards you’ll probably have a few additional situations where you want to double down. Once you master basic strategy and learn how to use your chosen system you need to memorize the index plays for your system. If you need to double more or less based on the count they’ll tell you what to do.
Don’t worry about counting or doubling rules based on the count until you have the basic strategy and doubling decisions down perfect.
Knowing when to double down is an important part of basic strategy and reducing the house edge. Always check the table rules before you start playing so you know exactly when you can and can’t double. Then make sure you take advantage of every situation that calls for doubling covered above.