The House Edge in Blackjack: What You Should Know

Whether or not the dealer can hit on Soft 17s affects the house edge. A Soft 17 is a 17 with an Ace, which counts as either 1 or 11. This prevents the dealer from going over, since if they draw a card higher than 4 the Ace is counted as a 1. Some games allow dealers to stand on Soft 17s, while others require them to hit.

Even though the dealer seems more likely to bust by hitting on 17, when they don’t their hand advantage improves slightly. Blackjack hands in which the dealer hits on a Soft 17 have a 0.2% higher house edge than when they stand.

The more decks that are used in a blackjack game, the more the house edge increases. While this may seem surprising since the ratio of high and low cards is unchanged, the likelihood of getting a blackjack is reduced by the increase of decks.

For example: Say you’re dealt an Ace in single-deck blackjack. You have a 31.7% chance of hitting blackjack when you’re dealt an Ace in single deck games, since 16 of the remaining 51 cards are worth 10 (16 ÷ 51 = 31.7%). 

But those odds drop to 30.8% if you’re playing eight-deck blackjack, since 128 of the remaining 415 cards are worth 10 (128 ÷ 415 = 30.8%).

While this only represents a 0.9% increase in house edge, over the long run it can add up to a lot of money.

The more flexible you can be when splitting hands, the more you’re able to diminish the house edge in blackjack. Splitting a favorable pair gives you two strong hands to work with, reducing the house edge between 0.1% and 0.2% in the process.

Many casinos only allow you to split once. But some let you split again if you’re dealt another pair of identical cards; which reduces the house edge another 0.01%. And if you’re allowed to split another time you can take away another 0.15%–0.2% from the house edge.

If you’re able to double down after splitting you can reduce the house edge by roughly 0.15%. Splitting a favorable pair of cards enables you to play both hands separately, one card at a time. And doubling down on two favorable hands positions you to potentially increase your profits by winning more money on two strong hands.

It’s worth mentioning that not all blackjack games allow players to double down after splitting, so be sure to check the table’s rules to make sure you’re allowed to do so.

The ability to remain flexible when doubling down can lower the house edge, since the more you can double down the more chances you have to potentially increase your profit. Most blackjack tables only allow you to double down on 10 and 11, and only permitting double downs on two numbers increases the house edge by about 0.2%.

Some blackjack games allow players to double down on 9,10, and 11, and the added opportunity lowers the house edge by approximately 0.15%. And if you can double down on any number, the house edge is reduced by another 0.2%.

Doubling down on its own won’t help you win more money, however, as you need to also have a solid grasp on simple blackjack strategy to increase your chances of winning more hands.

A lot of players overlook surrender options in blackjack, but when used correctly surrendering can trim the house edge. There are normally two types offered: early surrender and late surrender.

Early Surrender is when player forfeits half their bet before the dealer checks for blackjack. This is most often done when the dealer’s upcard is an Ace, and the player isn’t confident their dealt cards can win. Surrendering early shaves approximately 0.6% off the house edge.

Late Surrender involves the player forfeiting half the bet after the dealer checks for blackjack. Surrendering late doesn’t reduce the house edge as much as surrendering early does, but still cuts the edge down by roughly 0.05%.

A natural blackjack’s payout percentage significantly affects the house edge.

Traditionally a natural blackjack pays out 3:2, meaning that blackjack on a $10 bet would pay out $15. However, many casinos now pay natural blackjacks out at 6:5, meaning that same $10 bet would only win you $12.

6:5 payouts raise the house edge by 1.5%, which over time can really add up. It’s a good idea to check the natural blackjack payout percentage before playing, and if it’s 6:5 you’re better off trying to find a different table.

Insurance bets increase the house edge and are generally a bad bet for players, but what is insurance in blackjack? Insurance bets enable players to wager up to half the original bet by predicting that the dealer has a natural blackjack. These wagers pay 2:1.

The problem is that in a single deck game the dealer has approximately a 30.8% chance of having blackjack, which means there’s a 69.2% chance they don’t. Insurance bets add a significant 7.5% to the house edge, so more often than not it’s better to avoid insurance bets in blackjack.

Charging a fee to play blackjack dramatically increases the house edge. Some casinos charge $0.50–$1 per hand to play blackjack, and that doesn’t include whatever money you wager. So no matter the outcome of the hand, you lose money.

If a casino charges a $0.50 ante on a $5 bet, it automatically adds a whopping 10% to the house edge. And the only way to reduce that edge is to bet more money, as a $0.50 ante on a $100 bet adds a relatively low 0.5% to the house edge. While this is fine for high rollers, most casual players can’t afford such high per-hand wagers.

Simply put: if a blackjack table charges an ante fee, leave it and find a new one.