Getting the Edge at Blackjack

13 November 2022

By John Grochowski

On a lazy Tuesday morning, it was time for one of my regular conversations with Blackjack Bob.

Bob had seen my column explaining the house gets an edge on banker bets in baccarat and buy bets in craps by charging a commission. It seems Bob had his own recent conversation on the source of a house edge.

"I guess blackjack is a little more subtle than most games," he said. "I was talking with a guy who doesn't play as much as I do, but he's played off and on for 20 years or more.

"He told me it wasn't obvious to him why the house wins. The cards come out of the same deck with the same frequency, so why should the house win more than the player?"

Because the player acts first, I replied, knowing that Bob has understood that for decades.

"Exactly," Bob said. "Players get the chance to bust first, and if they do, they lose regardless of what the dealer does. If both bust, the house wins."

I elaborated.

If both player and dealer make their hit/stand decisions by dealer rules, each would bust about 28 percent of the time. On about 8 percent of hands, both player and dealer bust. The dealer wins those hands. That's the house edge.

Bob picked it up from there. "Hardly anyone would play a game with a house edge that big. They might not understand why they were losing so much so fast, but they'd understand their dwindling stacks of chips."

I told Bob this was leading us right back to a discussion we'd had a couple of months ago when he encountered a player who insisted a mimic the dealer strategy was the way to go and that double down and pair splitting rules were traps.

In reality, giving players options on hitting, standing, splitting and doubling down, along with paying extra on blackjacks, are how the house gives enough back to players to make blackjack playable.

"Right," Bob said. "We don't need to dive back down that rabbit hole. What interested me this time is the source of the house edge and that someone who's played a long time didn't understand where it came from.

"In other games, it's usually more obvious. Take roulette. With double-zero, there are 38 numbers, so odds against a single-number winning are 37-1. The payoff is only 35-1. The gap between 37-1 and 35-1 is the house edge."

I chimed in that the house edge derives from paying less than true odds on any game, including blackjack. You have a less than even chance of winning a hand, but except for two-card 21s, the payoffs are only even money.

Bob asked, "What other games are more subtle at how they arrive at paying less than true odds? I know craps and roulette from having played a long time, but I don't play everything. You know I stick to blackjack."

Some players might think the edge source isn't obvious on poker-based games such as Three Card Poker or Caribbean Stud. In the ante-play against the dealer portions of those games, the edge comes from the qualifying hand concept. If the dealer doesn't have a designated minimum hand, only antes are paid, and play bets are pushes. Not all winners are paid, leading to the house edge.

"I can see why some players wouldn't pick up on that right away, though having a winner that gets partial payment seems like a big hint," Bob said.

"But you know what? When I explained the blackjack edge, my friend told me, 'You always did overthink it.' Heck, I'm just thinking it."