Doubling Down for Less in Blackjack

“Doubling down for less” is an unusual move at the blackjack table, and it’s usually a mistake. But since most people never do it, it’s a mistake most players never make. This post looks at how doubling down for less works in a game of blackjack and whether it’s a good time.

An Example of Doubling Down for Less

Suppose you’re betting \$100 per hand at the blackjack table, and you get dealt a hard 11 total. Most blackjack players familiar with basic strategy know that the correct move in this situation is to double down.

To double down, you put up more money (the same amount you bet initially) and agree to take only one hit. In this case, if you bet \$100, you would put up another \$100 and tell the dealer you’re doubling down.

But let’s suppose that the dealer has a 10 showing as her face-up card, and you’re nervous about how good the dealer’s hand might be. You might decide to “double down for less” by putting up \$20 or \$50 instead of the full \$100.

You’re still agreeing to take one, and exactly one, additional card.  You’re also still getting more money into action. Most blackjack players I know don’t even know that this is an option. In fact, I didn’t know about it until I read an article online.

I’ve personally never seen anyone do this. But it’s something you can do. Unfortunately, doubling down for less is also the wrong move to make, and the math behind why isn’t as complicated as you might think.

Why the Math Makes Doubling Down for Less the Wrong Move

You basically have three realistic decisions in the example situation.

1. You can hit the total of 11.
2. You can double down on the total of 11.
3. You can double down for less on the total of 11.

Theoretically, you COULD stand on a hard total of 11, but that’s obviously the wrong play. There’s no downside to getting another card. It’s impossible to bust a total of 11 by taking another card, so it’s ALL upside.

What Happens If You Just Hit the 11?

You’ll win 56% of the time. This means that your expected value here is excellent. If you win 56 times for every 44 losses, you’ll see a profit of \$1200 (on average) over 100 hands. You have 56 wins of \$100 each compared to 44 losses of \$100 each. That’s an average win per hand of \$12.

What Happens If You Double Down on the 11?

You’ll still win most of the time, but the win ratio will drop to 54% because of the extra card. But this time, you’ll have \$200 in action on each hand instead of \$100 in action on each hand.

54 wins at \$200 per win is \$10,800. 46 losses at \$200 per loss is \$9200. Your profit over those 100 hands is \$1600 instead of \$1200. Even though you’re losing slightly more often, your net profit over 100 hands is significantly higher. You’re winning an average of \$16 per hand instead of \$12 per hand.

What Happens If You Double Down for Less on the 11?

Your win ratio will be the same, because you’re still taking just one card, 54%. But now, you have less money in action. Let’s assume you double down for less by putting up \$50. Now, over 100 hands, you’re looking at 54 X \$150 in winnings, or \$8100.

You’re also looking at 46 X \$150 in losses, or \$6900. That’s \$1200 in net profits, which is the same profit you’d show if you just took a hit. But \$50 isn’t the only amount you could change your bet by.

You could go lower, to \$25, or higher, like \$75. Would either of those be more optimal? With a \$125 bet on the table, you’re looking at 54 X \$125, or \$6750, in winnings versus 46 X \$125, or \$5750, in losses.

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Your net win is \$1000, or \$10 per hand, which means that doubling down for less with an extra bet of \$25 provides you with an even lower expectation than just hitting.

What about with a bet of \$75? Now, you’re looking at 54 X \$175, or \$9450, in winnings, and 46 X \$175, or \$8050, in losses. Your net win is \$1400, which is better than what you’d see if you bet \$150, but still not as good as if you’d actually doubled down where your net win was \$1600.

Any of these can be divided by the 100 hands to get an average win per hand:

• Just hitting is an average win of \$12 per hand.
• Doubling down is an average win of \$16 per hand.
• Doubling down for less is an average win of less than \$16. The less you double down for, the lower the expected win.

The Moral of This Blackjack Story

The more of this blackjack story is similar to the moral of most blackjack stories: You should always stick with basic strategy. The basic strategy for blackjack is the mathematically optimal way of playing those hands. When you deviate from basic strategy, you might be okay in the short term. But in the long run, deviating from basic strategy does one of two things every time.

1. It increases the amount you’ll lose over time when playing a specific hand a specific way.
2. It decreases the amount you’ll win over time when playing a specific hand a specific way.
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The ONLY time you should deviate from basic strategy is when you’re counting cards.

Card counting is beyond the scope of this post, except as it relates to the doubling down for less move. But I can tell you this. You would never double down for less no matter what the count was.

I did see someone ask if it would make sense to double down for less if you don’t have enough of a bankroll to double down. For example, what if you’re playing for \$100 on that hand, but you only have \$50 left on the table besides that?

In that case, then yes, doubling down for less WOULD be the appropriate move. But I’d also suggest that if you only have \$150 on the table, you shouldn’t bet \$100 of it on a single hand of blackjack. You’d be better off betting \$10 per hand so that you could make the correct basic strategy decisions.

Conclusion

Deciding whether doubling down for less in blackjack is a good move is a great example of how the math behind basic strategy works. Once you know the percentage of times you’ll win with a certain move, and the percentage of times you’ll lose with a certain move, you can just do some quick multiplication and division to come up with an average profit or loss per hand.

Did you even know that doubling down for less was an option? Have you ever tried it? I’d love to read your comments below.