Apr 20, 2020
Apr 20, 2020

What is doubling down in Blackjack?

Blackjack doubling down strategy

Doubling down offers an exciting way to boost your winnings during a game of Blackjack if you are confident that are you are on verge of getting a strong hand. So what is doubling down, when are you allowed to do it and when should you? Read on to find out.

What is doubling down in Blackjack?

If a player decides to double down after receiving their initial hand, it means they have decided to double their original bet on the agreement that their hand will only receive one more card. Once the player’s hand is hit with the third card, their turn for that round is deemed finished.

A player is allowed to double down after they have been dealt their first two cards. Generally, you are not allowed to double down if you get Blackjack, hit or place an insurance bet, although you are often allowed to double down on a split hand. You are allowed to double down as many times as you want during a game of Blackjack, but you can only do so once per round.

As a result of its name, players often incorrectly assume that doubling down involves adding a further two cards to your hand or entering two hands in the same round (this is in fact splitting and the player needs to be initially dealt two cards of the same value in order to do it).

When to double down in Blackjack

The vast majority of Blackjack strategies will recommend always doubling down if your first two cards have a value of 11. This gives you an approximate 53.8% chance of finishing your turn with a strong hand containing a value of 18 or higher, and around a 30.4% probability of finishing it with a hand valued at 21.

It is advisable to also double down if your initial hand is worth 10 (including if it is comprised of two fives), with the exception of if the dealer’s face up card is worth 10 or an Ace and they therefore have a chance to get Blackjack. If your initial hand is worth nine, then probability dictates you should double down if the dealer’s face up card is three to six: essentially, when they are most susceptible to going bust.

If you have a soft hand containing an Ace and a card worth eight or lower, then it is sensible to double down when the dealer’s face down card is between certain values, again when they are at the greatest risk of exceeding 21. The information discussed in the last few paragraphs is summarised in the table below:

Blackjack double down strategy

NB: This table assumes four to eight decks in play and that the dealer hits on a soft 17.

When not to double down in Blackjack

With the exception of when your initial hand is worth 11, under no circumstances it is advisable to double down if the dealer’s face up card is worth 10 or an Ace.

In both of these scenarios the dealer will have the aforementioned approximate 53.8% chance of getting a strong hand worth at least 18 (plus around a 30.4% probability of getting Blackjack if the first card is an Ace). A hand with a value other than 11 is incapable of matching this probability, ultimately handing a significant advantage to the dealer.

Likewise, you should never double down on a hard hand that does not have a value between nine and 11. For values greater than 11, the probability of going bust will always exceed the chance of getting a strong hand with a value between 18 and 21.

Conversely, doubling down is not a logical approach for values less than nine, as you will be limiting yourself to a poor maximum potential value for your hand.