The Three Biggest Mistakes You're Making at Blackjack: Part 1

They're an essential part of basic blackjack strategy. Every good book on the subject of blackjack, and every strategy card you look at, will tell you to do them. And yet every day I see people ignore these basic moves, and it costs them money. Even players who think they know something about the game make these costly errors.

They're the three biggest mistakes you can make at blackjack. And in this and the next two installments, I'll tell you why.

First up:

1. Not hitting a 16 against the dealer's 9, 10 or Face Card.

The most money I see players leave on the table is because they ignore this part of strategy. Players are simply afraid to hit a 16 because it's the easiest hand in blackjack to bust; hit any card bigger than a 5 and your hand is history. Even players who will blithely hit a 15 without a second thought are reluctant to hit a 16.

I've even had a player stand on a soft 16 [an Ace-5] and proudly tell me "I never hit a 16!" But that guy was an idiot. This is one reason I prefer sitting at first base; otherwise some fool to my right will stand on their 16 when I want to double down on a 10 or 11, and I'll be stuck taking the 4 or 5 they should have hit.

I'll have players tell me they always stand on 16 and they're doing just fine. They're lying. Because (here's the bad news) if you have a 16 and the dealer is showing a Jack, you're probably going to lose no matter what you do. But in the long run you'll lose less of the time if you hit your 16 instead of standing on it. And losing less is the same as winning more.

So, if you're looking at a 9 or a 10, and you have a 16, you just have to hit it. Why?

Because the math says so, and blackjack strategy is all about the math.

Let's start by assuming you have a 16 and the dealer is showing a 9. There are 13 different cards in a blackjack deck (2,3,4,5,6,7,8,9,10,J,Q,K,A). If you have a 16 and the dealer is showing a 9, that means that more than half of the cards that the dealer can have in the hole already have you beat: 8,9,10,J,Q,K,A. Therefore, more than half of the time, you're already beat if you don't try taking another card to improve your hand, and so you have nothing to lose by taking the hit. And more than half the time is all you need to be profitable in the long run.

If you're looking at a 10 or a face card, the situation is even worse if you want to stand. Since if you're in this situation, the dealer has already checked to make sure her undercard wasn't an Ace, which means instead of 7 cards out of 13 giving her a winning hand, it's 7 cards out of 12 (7,8,9,10,J,Q,K), making the odds against her busting even worse.

By the way, let's assume you decided to stay on your 16 and got lucky: you were right and the dealer has a hand that she has a chance of busting (12,13,14,15,16). 

Here's a fun fact: Every bustable hand has exactly five cards that will make them a made hand on the first card drawn. The odds of the next card being any particular card are approximately 7.7%, so that means in the less than half of the time that the dealer has a bustable hand under their face card, they have a 38.5% chance of making a hand.

It also means that when you're faced with a dealer's 9 or 10 against your 16, you still have a 38.7% chance of making a hand on your first hit instead of busting. And while these aren't the best odds in the world, they're better than the 0% chance of winning which you will have more than half of the time.

By the way, I would do the same against the dealer's 8 or 7. What actually got me started working out the math on these hands on my hour-long bus rides to the casinos in Cripple Creek was a conversation I had with a player who never hit her 16 against the dealer's 8. She said her dad told her that when the dealer's showing an 8, he only has a made hand less than half of the time. I figured out the math, and, well, her dad's right up to a point: If the up card is an 8, less than half the cards in the deck that can be his undercard make him a hand (9,10,J,Q,K,A). Well, by the same logic that I hit against a 10, I should stay against an 8, right?

Uh, no. Because whether he already has you beat isn't the only thing you have to worry about. If he has a 2 or 3 in the hole, then he has a hand so good, you'd double down if you had it. Not taking the next card because you're afraid of busting on a 6 through 10 wouldn't do you any good in that case. So the chances of the dealer having a strong card under an 8 actually go from 46.2% (made hands) to 61.6% (adding the 2 or 3). What if his undercard is a 4? A 12 is actually a strong drawing hand, because less than 1 out of 3 cards will bust him on his first hit. So give him a 69.3% chance of having a strong drawing hand. Even in the best possible scenario...that he has an 8 in the hole, meaning he also has a 16...remember, he still has a 38.5% chance of making a hand on his next card. So cumulatively, the odds say staying against that 8 is a horrible idea.

I'd do the same against a 7, even though it's the most marginal of these cases (fewer times he'll have a made hand), because the dealer has one more hole card that could give him a strong draw.

So next time you have a 16 and the dealer's showing a King, go ahead and take the hit. Show no fear. There's no room for fear in blackjack.