The power of 20

9 October 2016

By John Grochowski

QUESTION: I just left a blackjack table where it seemed like nobody could win with a 20. One hand, three of us had 20s and the dealer had a blackjack. Three times within five hands I was dealt 20s. On one, the dealer also had a 20, and on the other two she pulled 21s. Other players were having that kind of luck, too.

You know how frustrating that can be. One of the other players said, “When you can’t win with 20, it’s time to go.” The dealer was an old veteran who looked to be in his 60s, and he said, “I see this all the time. Twenty is not a winning hand. It loses as often as it wins.”

That’s surely an exaggeration. Twenty has to win more than it loses, doesn’t it?

ANSWER: Players win with 20 a lot more often than they lose, and that’s true against every possible dealer face-up card.

Dealers have blackjacks on about 4.8% of hands and make multi-card 21s on about 7.4%. They make 20 on about 17.6% of hands. That means your 20 will win about 70.2% of the time, lose on 12.2% and push on 17.6%.

Twenty is a profitable hand for players against every dealer face up card. At wizardofodds.com, Michael Shackleford has a chart of expected profit or loss for each player two-card total against each dealer up card.

Let’s look at player 10-10 vs. each dealer possibility in a six-deck game in which the dealer hits soft 17.

The least profitable situation comes when the dealer has a 10 up. The player’s average profit when standing on 10-10 is 56 cents for each dollar wagered – and that’s an outcome I’d take any time.

Average player profits per $1 wagered are 60 cents vs. Ace, 63 cents vs. 2, 64 cents vs. 3, 65 cents vs. 4, 67 cents vs. 5, 68 cents vs. 6, 77 cents vs. 7, 79 cents vs. 8 and 76 cents vs. 9.

Those are all healthy profit levels. A player 20 is not a sure thing. It will lose some hands and there will be streaks where a hot dealer beats everything. But the dealer’s statement that “20 is not a winning hand” is incorrect.


QUESTION: A question about the field bet in craps: I see a lot of tables that pay 3-1 on the field when the shooter rolls a 12, but 2-1 on 2 and even money on the other numbers. I swear I once saw a table in Reno that did it the opposite way, with 3-1 on 2 but 2-1 on 12.

Have you ever seen that? Does it make a difference in the odds?

ANSWER: I also once played at a Reno table that had the payoffs you describe, with 3-1 on 2, 2-1 on 12 and even money on the other field numbers – 3, 4, 9, 10 and 11.

Regardless of whether the 3-1 payoff is on 2 with 2-1 on 12 of if those are turned to 3-1 on 12 and 2-1 on 2, the house edge is 2.78%. It’s more common for the bigger payoff to be on 12, but the odds are the same either way.

Both ways are much better than when both 2 and 12 pay 2-1 on field bettors. On such tables, the house edge on the field is a whopping 5.56%.

In an extremely rare case, an Illinois casino in the late 1990s paid field bettors 3-1 to on BOTH 2 and 12. That made it a break-even bet with no house edge.