Home | Learn | Blackjack | Double Trouble? How to Double Down in Blackjack

Double Trouble? How to Double Down in Blackjack

June 5, 2022

Even if you don’t play casino games, chances are you’ve heard of the double down blackjack bet. If you’ve ever heard someone describe themselves committing to a decision as “doubling down on” it, that’s an idiom that has entered speech from the blackjack bet.

What does double down mean?

When you double down in online blackjack, you double your original bet in exchange for one further card. It’s a bold strategy, since if you get a low card then you can’t hit again. Instead, you’ll be stuck on a poor total and unable to reach 21. However, doubling down can also be one of the most profitable plays in blackjack. If you win, you receive a payout based on your doubled bet.

When can you double down in blackjack?

In blackjack, you’re allowed to double down after you’ve placed your bet and the cards have been dealt. If you’ve already decided to hit or stand then you can’t double down afterwards. You need to decide whether or not to double down as your first decision in the hand.

So when is best to double down? Fortunately, blackjack strategists have mapped out the mathematical scenarios that generate the best returns – including when to double down. The exact strategy depends on which blackjack variant you’re playing.

Generally, though, there are three situations in which you should always consider a double down bet:

When you have 11

Having a total of 11 in your first two cards is a very strong position. In an eight-deck game of blackjack, if you have an 11, there are up to 32 cards that can give you an unbeatable 21. Additionally, there are up to 24 cards that can give you 18 or higher, which is generally a winning hand.

An 11 is such a strong hand that even if the dealer has a 10, you should still double down. If the dealer stands on a soft 17, then you should even double down even if the dealer is showing an ace. Even though you might run into blackjack, you’ll still be making a profitable decision in the long run.

When you have a soft 16 to 18

If you have an ace and a 5, 6 or 7 then you have a “soft” hand. This means that the value of the hand can change depending on whether an ace is played as 1 or 11.

Against a low dealer upcard, choosing to double down gives you a strong chance to hit a hand of 17 or higher. If the dealer has a low card, this total is generally profitable – so it’s a good time to double your bet.

When you have a hard 9 or 10

When you are dealt a hard 9 (a hand with no ace) then doubling down is profitable if the dealer’s upcard is a 6 or lower. Against a 7 or higher, you should simply hit on a hard 9 regardless of whether or not the dealer stands on a soft 17.

With a hard 10, you should be doubling down against any dealer upcard of 9 or lower. Against aces, face cards and 10s, doubling down with a hard 10 is no longer profitable.

The double down blackjack bet explained

When should you not double down?

The different variants of blackjack mean that there are few hard and fast rules. However, there are a couple of situations in which you should never double down.

If your total is higher than 11, do not double down. The same frequency of high cards that makes doubling down on 11 profitable is what means doubling down on 12 or higher is blackjack suicide. The risk of busting is far too high, especially with a doubled bet.

Additionally, if the dealer is showing an ace, then you should never double down – unless they have to hit on a soft 17. In that case, when you have 11, you should double down against any dealer upcard.

What about doubling down after a split?

In blackjack, splitting means dividing your hand into two separate hands at the cost of an extra bet. You can only do this when your hole cards are of equal rank. Generally, you will still be able to double down after you have split, because your split hands are treated as two separate hands.

The exception to this rule is if you split A-A. Most casinos will generally not allow you to double down after splitting aces, and in fact you can often only hit once per hand after doing so.

Bear in mind that if you double down both split hands, your total investment will be four times your original bet – so be sure you’re in a strong position before you do!

How do you signal double down?

When you’re playing blackjack online, doubling down is as simple as pressing the button. However, when you’re playing live blackjack in a real casino, you won’t have this luxury.

Fortunately, there’s nothing too complicated about signalling a double down. All you need to do is put a stack of chips matching your original bet next to your initial bet. The dealer will know you want to double down and will deal you one further card. Hopefully it’s a 10!