Blackjack Double Down

Blackjack is one of the casino games with the lowest possible house edge, which can be attributed to its favourable set of rules. One such rule that works to the benefit of players is the double down option. It enables you to increase your initial bet when you find yourself in advantageous situations.

Doubling down can be both exciting and profitable for the player provided that they know when to make this move correctly. The situations when this play becomes optimal do not occur all that often at the blackjack table. One must learn to identify them in order to extract the most value from doubling their wagers.

Regrettably, many blackjack players do not recognize the correct spots that call for a double down and end up losing tons of money as a result. In this article, GamblingPlex expands on what doubling down is in blackjack, provides readers with some strategy hints for this move, and explains why you should never double down for less than your original wager.

• ✓ How to Double Down
• ✓ The OBO Rule
• ✓ Choosing a Blackjack Table
• ✓ When Should You Double Down
• ✓ Doubling on Hard Hands
• ✓ Doubling on Soft Hands
• ✓ Should You Double for Less?

How to Double Down in Blackjack

To begin with, doubling is available to players only on their starting hands before they have drawn any more cards to their initial totals. When a player wishes to double their bet in the game of blackjack after their hand has been dealt, they can do so by signalling they want a double down. The hand signal used in shoe games differs from that in single-deck and double-deck variations.

In multi-deck blackjack where the cards are dealt out of a shoe, you double down by posting an additional wager up to the amount of your original wager and pointing towards your betting box. You place the extra chips in your betting box next to your initial bet but never on top of it.

This is for the benefit of the dealer, allowing them to easily distinguish your double down wager from your original bet. The dealer will then draw no more than one card to your starting hand. The third card is usually placed perpendicularly, next to the first two cards, to indicate this hand has been doubled on. There will be no more cards dealt to that particular hand.

When playing single-deck and double-deck blackjack, you double down by making an extra bet and placing your first two cards face-up on the layout. The dealer would then tuck the third card under your chips.

The third card is dealt face-down in this case and is exposed after the dealer has finished playing their hand. This further adds to the excitement of doubling, especially when the dealer busts. With that said, players in hand-held games are permitted to peek under the double-down card to see its value but should do so without exposing it. The profits or losses you register during this round are based on the new overall wager.

For example, if you had initially wagered $10 and have doubled for the full amount of $10, you now have a total of $20 in action and will win $20 on top of that, for an overall payout of $40. If the dealer beats you, you will lose $20 rather than $10 only.

The OBO Rule

This is not the case in many European variations where no hole cards are in play. The dealer receives one exposed card during the initial deal and does not draw a second one until after all patrons have finished playing their hands.

Such games usually implement the so-called “original bets only” rule, abbreviated as OBO. Whenever the dealer hits a blackjack, players would lose only their initial wagers under this rule. Additional bets made on doubling and splitting push and are returned to players.

Choosing a Blackjack Table

Doubling is an interesting choice, and it could pay quite well when done properly. However, you should not forget to check the specific rules that apply to doubling at your chosen table before you sit down. Blackjack is infamous throughout the gambling world for its diversity when it comes to rules. Playing conditions would often vary not only between different casinos but between different blackjack tables within the same gaming venue.

Before you sit down, check whether you can double on any two cards or just on hands with totals of 9, 10, and 11. When restricted to doubling only on these three hands, players suffer a house edge increase of 0.09%. Some tables are even more restrictive, allowing you to make this play only on two-card totals of 10 and 11, which adds 0.18% to the casino advantage.

Another thing worth checking beforehand is whether the table supports doubling after a split (DAS). The absence of DAS also leads to an increase in the house edge, this time by 0.14%.

Keep in mind that the exact doubling rules, applicable at a given table, are not displayed on the layout as is the case with the dealer’s standing total and the blackjack payouts. We suggest you ask the dealer or the pit boss before you take a seat if you are unsure whether you can double on any two-card hand.

When Should You Double Down?

New players usually rely more on their hunches and intuition when doubling, which often leads to bad decision-making and unnecessary frustration. As exciting as it is, doubling is not the optimal move at all times. This play is recommended only on specific two-card hands against certain upcards that put the dealer in a weak spot.

It makes no sense to increase your wager against a dealer who shows strong upcards, if you, yourself, have a bad starting total like 12 or 15, for example. One situation where doubling down has been proven to show the best results is when a player is holding a total of 11 against a dealer with a 6. The probability of the dealer busting with this upcard is a little over 42%.

Meanwhile, your chances of prevailing with a total of 11 against the 6 are inevitably higher than 50% regardless of the exact composition of your hand as you can see below. Doubling down when the odds are on your side will have an overall positive effect on your profitability. The figures correspond to a six-deck S17 game where the peek rule is in place.

The optimal plays for doubling are covered by basic strategy, which is presented in the form of a chart. You can start seeing more profits from your double downs if you stick to basic strategy. Feel free to consult with your strategy card when playing online or at a landbased casino until you learn all the correct moves by heart.

Doubling on Hard Hands

Before we proceed any further with strategy hints, we would like to specify that the correct doubling moves may differ, depending on whether you have a hard or a soft total. A hard hand is one that either lacks an ace or has one, but its value is 1 only.

Doubling on hard totals of 12 or higher is never recommended since your chances of busting are greater and you risk losing twice as much money. The higher the hard total, the higher your chances of going over 21 by drawing a third card.

You can find the correct moves for doubling below but keep in mind they correspond to six-deck games with DAS under the S17 rule for the dealer. Some of the playing decisions are different when you double against a dealer who hits soft 17 (H17). Certain moves also vary based on deck number. Refrain from using multi-deck strategy cards for single-deck and double-deck blackjack to prevent potential playing errors.

• Double down on hard 9 when the dealer’s exposed card is 3, 4, 5, or 6.
• Double down on hard 10 against all dealer upcards except for 10 and ace. This applies also when you get dealt a pair of 5/5, which you should never split. You double down on your 5/5 against dealer upcards 2 through 9, instead.
• Double down on hard 11 against all exposed cards of the dealer except for the ace. On a side note, players are recommended to double even against the dealer’s ace in shoe-dealt H17 blackjack.

Doubling on Soft Hands

Soft hands call for a different approach because they contain aces whose value fluctuates. The aces can be assigned a value of either 1 or 11, based on the holder’s preferences. You have more chances of making successful doubles with such hands because the ace’s flexibility prevents you from going over 21 by taking one more card from the dealer.

The worst that could happen is for you to get dealt a small-value card and end up with a low hand total. It is also possible to catch a ten-value card and transform your hand from a soft one into a hard one.

Here is an example. You have A/5, or soft 16, which you can treat as either 6 or 16. The dealer’s upcard is a 6 which calls for soft doubling. The dealer pulls out a King for your double down and you get stuck with a hard 16. Check out the plays recommended below. They are again optimal in multiple-deck blackjack where the dealer is required to stand on soft 17 (S17).

• Soft 13 (A/2) and soft 14 (A/3) require a double down when the dealer’s exposed card is 5 or a 6.
• Soft 15 (A/4) and soft 16 (A/5) call for a double when the dealer shows a 4, 5, or 6.
• Soft 17 (A/6) and soft 18 (A/7) require a double when the dealer’s upcard is 3, 4, 5, or 6. In H17 games, you double on soft 18 against the dealer’s deuce as well. Soft 19 (A/8) also calls for a double down against the dealer’s 6 in H17 games.

Should You Double for Less?

As we told you earlier, you can double down for an amount up to your original wager although no one prohibits you from doubling for less than what you have initially bet. For instance, if you have originally wagered $20, you can double for $15, $10 or even $5.

In fact, this is possible in almost all landbased casinos. However, you must always double for the full amount when playing online randomly generated variations of blackjack. Many rookies or players with tight bankrolls prefer to double for less, mainly because they feel uncomfortable with exposing more money at risk by covering their initial wagers in full. Others skip on doubling altogether by hitting or standing, both of which do not require them to invest more money.

How Doubling Compares to Hitting

It is no coincidence doubling down is recommended over hitting and standing in certain cases. You are entitled to no more than one card when doubling, which is why you sometimes get stuck with bad stiff hands like hard 15 or hard 14.

Since it is impossible to hit after a double down, the percentage of the times when you beat the dealer with doubling is smaller than that for hitting. However, the small difference in win rates is offset by the larger profits you receive for successful doubling.

Suppose, for instance, you receive a total of 11 against a dealer with a ten-value card. As you can see from the strategy hints, this situation calls for a double down in shoe games with the S17 rule. Your 11 will win against the ten-value card 56 per every 100 hands if you hit and 54 per every 100 hands if you double down.

Respectively, you will have 54 x $20 = $1,080 in earnings, if you double for the full amount on a $10 initial wager. Your losses with 11 against the dealer’s ten-value card will be 46 x $20 = $920 on average. You will win approximately $160 every hundred hands in the long term.

Meanwhile, your earnings when you hit your 11 against the dealer’s ten will amount to 56 x $10 = $560 whereas your losses will be 44 x $10 = $440. Thus, hitting yields net profits of $120. This leads us to the logical conclusion doubling on 11 against the dealer’s 10 is better for the player than hitting because it yields $40 more in profits per every hundred hands on average.

Doubling for Less vs. Doubling for the Full Wager

Similarly to hitting your 11 against the dealer’s ten, doubling for less on this hand is nonsensical from a basic-strategy perspective. The whole purpose of doubling is to enable the player to boost their gains when in favourable situations. This is impossible unless you double down for your full wager.

This becomes blatantly obvious when we continue with our example where your main bet is $10. Only this time, you choose to double for $5 only instead of hitting. Your average earnings per one hundred hands will be equal to 54 x $15 = $810 whereas your average losses will be 46 x $15 = $690 if OBO is not in place.

This makes for overall net winnings of $120, which is again $40 less than the average earnings you will register when you double for the full amount. This sum will drop further down if you are a scrape enough to double down for one-fourth of your initial $10 bet, or $2.50.

In this scenario, your average wins per one hundred hands will amount to 54 x $12.50 = $675 whereas your losses will add up approximately to 46 x $12.50 = $575. Your total of 11 will earn you only $100 against the dealer’s ten in the long run.

It is easy to see why doubling for the full amount is the best course of action, compared to hitting or doubling for less. This applies to all correct doubling plays, not only to a total of 11 against a ten.