What Is the House Edge in Blackjack? The Real Numbers Behind the Game

Ask ten people what the house edge in blackjack is and most will say “half a percent.” That answer is close enough to be useful and vague enough to cost you money, because the number is not fixed. It moves with the table rules, the payout on a natural, the number of decks, and how well you play.

This article breaks down where the house edge comes from, what each common rule is worth in percentage points, and how to read a blackjack table before you put money on it. The figures come from published mathematical analysis, mostly from gambling mathematician Michael Shackleford’s work at Wizard of Odds, which casinos and players both treat as the reference standard.

If you play blackjack casually and want to stop guessing whether the game in front of you is a good one, this is for you.

What Is the House Edge in Blackjack, Exactly?

The house edge is the ratio of your average loss to your initial bet. If a game carries a 0.5% edge, every $100 you put out as an opening wager costs you 50 cents on average across a huge number of hands.

Two details matter here.

First, the edge is measured against your opening bet, not everything you eventually push into the circle. Money added by doubling and splitting is left out of the denominator, which makes the house edge slightly overstate the risk relative to total money wagered. Shackleford tracks that second figure separately and calls it the element of risk. Under Atlantic City rules, the house edge is 0.43% while the element of risk is 0.38%.

Second, every house edge number you see assumes correct play. Play worse, and the real edge against you is higher.

Why Does the Casino Have an Edge in Blackjack at All?

Both sides draw from the same shoe. Both are trying to get closer to 21. So where does the advantage come from?

The Player Acts First

You play your hand before the dealer plays theirs. If you bust, your bet is collected immediately, and it does not matter what the dealer does afterward. In a symmetrical game, a double bust would be a push. Instead the house keeps the money.

Players bust roughly 28% of the time under basic strategy, and so does the dealer. Multiply those and you get around 8%, which is the rough size of the built-in structural advantage before any other rules are applied. Treat that 8% as a back-of-envelope estimate rather than a precise figure, because the two bust rates are not fully independent.

What the Rules Give Back

Almost every other rule in blackjack tilts toward the player. A natural pays 3 to 2 while the dealer’s natural only takes your single bet. You can double down when the situation favors it, and the dealer cannot. You can split pairs. You can stand on 16 when it makes sense, while the dealer is forced to hit. At some tables you can surrender.

Stack all of those against the double bust penalty and the net comes down to a fraction of a percent.

What Is the House Edge With Perfect Basic Strategy?

Under the best commonly available rule sets, the house edge is remarkably small. Liberal Vegas Strip rules (dealer stands on soft 17, double on any two cards, double after split, resplit aces, late surrender) produce a 0.28% house edge with correct basic strategy. Atlantic City rules come in at 0.43%.

For comparison, using the same source’s figures: the banker bet in baccarat carries a 1.06% edge, the pass line in craps 1.41%, single-zero roulette 2.70%, and double-zero roulette 5.26%. Blackjack played properly is one of the cheapest bets on the floor.

Play it improperly and it stops being cheap. Shackleford analyzed three popular bad approaches under Atlantic City rules: never busting (never hitting a hard 12 or higher) gives the house 3.91%, mimicking the dealer’s hit and stand rules gives up 5.48%, and always assuming the dealer has a ten in the hole costs 10.03%.

That is the real spread. The difference between a 0.43% game and a 5.48% game is not the casino. It is the person in the seat.

Which Blackjack Rules Raise or Lower the House Edge?

This is where the answer gets specific. The figures below show the effect of each rule on your expected return, measured against a baseline of eight decks, dealer stands on soft 17, double on any first two cards, double after splitting allowed, and splitting to four hands. A positive number means the rule helps you.

Rules That Help You

• Single deck: +0.48%
• Early surrender against an ace: +0.39%
• Player may draw to split aces: +0.19%
• Double deck: +0.19%
• Six-card Charlie (automatic win with six unbusted cards): +0.16%
• Resplitting aces: +0.08%
• Late surrender against a ten: +0.07%

Rules That Cost You

• Blackjack pays 6 to 5: -1.39%
• Blackjack pays 7 to 5: -0.45%
• Dealer hits on soft 17: -0.22%
• Doubling restricted to 10 and 11 only: -0.18%
• No splitting aces: -0.18%
• No double after splitting: -0.14%
• European no hole card: -0.11%
• No resplitting: -0.10%

Notice the scale. Everything in that second list except the payout rule sits under a quarter of a percent. The payout rule is worth more than all the others combined.

How Much Does 6:5 Blackjack Cost You?

A lot, and it is the single most important thing to check.

Paying 6 to 5 on a natural instead of 3 to 2 costs the player 1.39%. That takes a decent game and roughly triples or quadruples the edge against you. Shackleford documented one single-deck game where the rules were otherwise strong enough to leave a 0.05% edge, but the 6 to 5 payout pushed the total house edge to 1.44%.

The maddening part is that these tables often advertise the good rules on the felt and put the payout in smaller type. Shackleford estimates around 10% of “21” tables in Las Vegas now pay less than 3 to 2, and argues that games paying less than 3 to 2 do not deserve to be called blackjack at all.

Run the numbers on a normal session. At 70 hands an hour and $25 a hand, a 0.5% game costs about $8.75 an hour in expectation. Move to a 6:5 version of the same game and you are near 1.9%, or roughly $33 an hour. Same table, same dealer, same free drinks, nearly four times the cost.

Does the Number of Decks Change the House Edge?

Yes, though far less than most players assume. Relative to an eight-deck game, a single deck is worth +0.48% to the player, a double deck +0.19%, four decks +0.06%, and six decks +0.02%.

Fewer decks help mainly because naturals come up slightly more often, and a natural pays a premium. The trap is that casinos know this. Single-deck games are frequently the ones carrying a 6:5 payout or restricted doubling, which wipes out the deck advantage several times over. A single-deck 6:5 game is worse than a six-deck 3:2 game, not better.

Continuous shuffling machines are a related wrinkle. A CSM slightly lowers the house edge compared to a cut card game, but because the dealer never pauses to shuffle, you play more hands per hour and lose more per hour overall.

Why Do Casinos Win Far More Than 0.5% at Blackjack Tables?

This confuses a lot of people who look up casino revenue reports and see blackjack “win percentages” in the double digits.

Those reports measure hold, not house edge. Hold is the ratio of chips the casino keeps to chips it sold, usually measured across a shift. If a table sells $1,000 in chips and players walk away with $700, the hold is 30%. Hold depends on how long people sit and how many times the same money is recycled through the game, which is why a mathematician cannot calculate hold from the rules alone.

Play $100 through a 0.5% edge fifty times and you have wagered $5,000. Your expected loss is $25, or a quarter of your buy-in, even though the edge per hand never changed.

Casinos also do not assume perfect play. One major Strip property’s internal player-rating table uses 70 hands per hour and a 0.75% average house edge for blackjack, higher than the theoretical figure because it accounts for the mistakes real players make.

Does Bad Play at Your Table Increase the House Edge?

No, and this one has actually been tested rather than argued.

Shackleford ran a simulation of 1.05 billion hands under liberal Vegas Strip rules with two players. The first played correct basic strategy and lost at 0.282%. The second played wildly incorrectly and lost at 11.260%. The correct player’s result barely moved regardless of what the second player did.

The person at third base who hits a 16 against a dealer 6 is hurting exactly one bankroll, and it is theirs. The card they took was as likely to have saved you as sunk you. What you remember are the times it went badly.

Can You Get the House Edge Below Zero?

Card counting is the only widely documented method that flips the edge, and it works by changing your bet size when the remaining cards favor you rather than by changing the game’s underlying math. It requires a countable game (a cut card and reasonable penetration, not a continuous shuffler), a bankroll that can absorb long losing stretches, and tolerance for being asked to leave.

Basic strategy does not beat the house. It gets you the smallest possible loss rate for the rules in front of you, which for most people is the realistic goal.

If memorizing a full chart feels like too much, there is a middle path. Shackleford published a simplified 21-cell strategy that costs only 0.14% in errors compared to full basic strategy under liberal Vegas Strip rules, roughly one extra lost hand every twelve hours of play.

Frequently Asked Questions

What is the lowest house edge in blackjack?

Under liberal Vegas Strip rules with perfect basic strategy, the house edge is about 0.28%. Getting there requires the dealer to stand on soft 17, doubling on any two cards, doubling after splits, resplitting aces, and late surrender, all with a 3 to 2 payout. Games this good exist but are not the default.

Does blackjack have the lowest house edge in the casino?

It is among the lowest for a game requiring no special skill beyond a strategy chart. Using the same reference figures, full-pay Jacks or Better video poker sits at 0.46%, Spanish 21 with the dealer standing on soft 17 at 0.40%, and the baccarat banker bet at 1.06%. Craps odds bets carry no edge at all, but they require a base bet with an edge first.

What is the house edge on 6 to 5 blackjack?

The 6 to 5 payout adds 1.39% to whatever the edge would otherwise be. A game that would be 0.5% becomes roughly 1.9%. Check the felt before you sit, and if it does not state the payout, ask the dealer.

What is the house edge on insurance in blackjack?

Insurance carries a house edge of 5.9% in a single-deck game, and it stays bad across deck counts. Taking even money on your own blackjack is the same bet in different clothing. Insuring every blackjack and every 20, a common habit, costs about 0.149% overall.

How often do you win a hand of blackjack?

Under basic strategy in a shoe game, you win roughly 42% to 43% of hands, push about 8% to 9%, and lose about 49%. Wizard of Odds figures put a win at 42.39% and a loss at 49.10%. The 3 to 2 payout on naturals plus winning doubles and splits is what closes most of that gap.

Is the house edge different for online blackjack?

The rules determine the edge, not the medium. Online and live dealer games publish their rule sets, so a six-deck game with the dealer standing on soft 17 and 3 to 2 payouts has the same edge whether it is dealt by a person or software. The practical difference is speed, since online games deal far more hands per hour and compound the same edge faster.

Does the number of players at the table affect the house edge?

Not mathematically. More players slow the game down, which reduces your hands per hour and therefore your total expected loss over an evening. Their decisions do not change your odds, as the billion-hand simulation above showed.

What to Check Before You Sit Down

Three things, in this order.

The payout on a natural. Look at the felt. If it says 6 to 5, walk. Nothing else at that table can make up for it.

Whether the dealer hits or stands on soft 17. Also printed on the felt. Standing is worth 0.22% to you.

Whether you can double after splitting. Worth another 0.14%.

Get those three right and you are almost certainly in a sub-1% game. Then bring a strategy card, keep it on the table, and use it. Dealers will not object, and it will cost you less than any betting system ever will.

One last thing worth sitting with: even a 0.28% game is a losing game over enough hands. Lowering the house edge changes how slowly you lose, not whether you do. Decide what an evening is worth to you before you buy in, and treat that number as the cost of the entertainment rather than a stake you expect to grow.