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Played correctly at a good table, blackjack costs about 0.5% per hand. Played by instinct at a bad one, it costs 3–4%. This hub explains the gap and where to start closing it.
Blackjack is the only mainstream casino game where a published, memorisable strategy reduces the house edge to a fraction of a percent — and the only one where the table rules printed on the felt change that edge by more than the strategy does. The CasinoTrust Academy blackjack section teaches both: the rules to look for and the decisions to make.
- ≈0.5%
- House edge, 6 decks, S17, DAS, 3:2, with basic strategy
- +1.39%
- Added to the house edge when blackjack pays 6:5 instead of 3:2
- ≈2%
- Extra cost of typical untrained play versus basic strategy
- 4.75%
- Chance of being dealt a natural blackjack in a 6-deck game
How blackjack rules change the house edge
Every blackjack table is a bundle of small rules, and each one shifts the house edge by a measurable amount. The figures below are the standard effects for a basic strategy player, relative to a baseline six-deck game where the dealer stands on soft 17, doubling after splits is allowed, blackjack pays 3:2 and there is no surrender. That baseline costs roughly 0.40% per hand.
| Rule | Good for the player | Bad for the player | Effect on house edge |
|---|---|---|---|
| Blackjack payout | 3:2 | 6:5 | 6:5 adds about +1.39%; 1:1 ("even money") adds about +2.3% |
| Dealer on soft 17 | Stands (S17) | Hits (H17) | H17 adds about +0.22% |
| Double after split | Allowed (DAS) | Not allowed | No DAS adds about +0.14% |
| Doubling restrictions | Any two cards | Only on 10 and 11 | Restriction adds about +0.18%; 9–11 only adds about +0.09% |
| Late surrender | Offered | Not offered | Surrender saves about −0.08% (S17) |
| Resplitting aces | Allowed | Not allowed | RSA saves about −0.07% |
| Number of decks | 1 or 2 | 6 or 8 | Single deck is about −0.48% vs 8 decks; 2 decks −0.19%; 4 decks −0.06%; 6 decks −0.02% |
| Dealer peeks for blackjack | Peeks (US style) | No hole card (ENHC), loses all bets | ENHC adds about +0.11% |
| Continuous shuffling machine | Neutral for basic strategy | Kills card counting | About −0.02% for basic strategy; large loss for counters |
The arithmetic is additive to a good approximation. An eight-deck, H17, 6:5 table with no surrender costs about 0.40% + 0.22% + 1.39% = 2.0% even with perfect play — four to five times the baseline. A single-deck table that pays 6:5 (common in Las Vegas) costs about 1.3% despite the "single deck" label. The blackjack payout matters more than everything else combined: never play 6:5.
Blackjack variants
"Blackjack" covers a family of games. The classic version is what basic strategy charts describe; variants change the rules enough to need their own strategy, and most carry a higher edge.
| Variant | Key rule differences | Approximate house edge (optimal play) | Notes |
|---|---|---|---|
| Classic / Vegas Strip | 4–8 decks, S17, DAS, peek, 3:2 | 0.35–0.45% | The reference game; use the standard basic strategy chart |
| Atlantic City | 8 decks, S17, DAS, late surrender, peek | ≈0.36% | Surrender makes this one of the best multi-deck rule sets |
| European | 2–6 decks, no hole card (ENHC), S17, double 9–11 only, no DAS common | 0.4–0.65% | Don't double or split against a 10 or ace as freely; see the strategy guide |
| Spanish 21 | 48-card decks (no 10-spot cards), late surrender, bonus payouts, player 21 always wins | 0.4–0.8% | Needs its own strategy; removing the tens hurts more than the bonuses help |
| Double Exposure | Both dealer cards face up, blackjack pays 1:1, dealer wins ties | ≈0.7% | The information is real; the ties rule takes it back |
| Blackjack Switch | Two hands, swap second cards; dealer 22 pushes; blackjack pays 1:1 | ≈0.6% | Own strategy chart; the push-22 rule is the cost |
| Pontoon | No hole card, 5-card trick pays 2:1, pontoon pays 2:1, dealer wins ties | 0.4–0.7% | Names differ (twist/stick/buy); strategy differs sharply |
| Free Bet Blackjack | Free doubles and splits, dealer 22 pushes | ≈1.0% | The "free" bets are funded by the 22 push |
| Perfect Pairs / 21+3 side bets | Optional side wagers on the main game | 2–11% depending on paytable | Avoid; they do not affect the main game's edge but cost far more per unit |
Why strategy works in blackjack and not in roulette
Roulette bets are placed before anything happens and each spin is independent, so no decision can change the odds. In blackjack you decide after seeing two of your cards and one of the dealer's, and the dealer's play is fixed by rule. That information has value. Standing on 13 against a dealer 6 (who busts about 42% of the time) and hitting 13 against a 10 (who busts about 21%) are not guesses; they are the choices that minimise loss in each situation, and the full set of them is basic strategy.
The blackjack strategies guide gives the complete chart for multi-deck S17 DAS games — hard totals, soft totals and pairs against every dealer up-card — explains why each line is what it is, covers the insurance bet, and gives an honest account of card counting including why it barely works online.
- Learn card values, the flow of a hand and every option in how to play blackjack
- Memorise the full basic strategy chart in blackjack strategies
- Check the exact probability of busting, improving or beating the dealer in any spot with the blackjack chance calculator
- Drill decisions until they are automatic with the free basic strategy trainer
- Look up any rule or term — DAS, ENHC, soft hand, penetration — in the casino wiki
Blackjack chance calculator
Enter your hand and the dealer's up-card to see bust probabilities and the expected value of each option.
Open the calculatorBasic strategy trainer
Deal random hands, make your decision, get corrected instantly. Ten minutes a day for a week is enough.
Start trainingBankroll management
How many units you need for a session, and how blackjack's low edge and high variance interact.
Read the guideBaccarat academy
The other low-edge table game: 1.06% on banker with no strategy required.
Learn baccaratOnline blackjack: RNG, live dealer and what to check
RNG blackjack reshuffles every hand from a full virtual shoe, which makes card counting pointless but keeps the edge exactly as advertised and the pace fast (200+ hands an hour). Live dealer blackjack uses a real eight-deck shoe dealt to about half its depth, runs 50–70 hands an hour at a seven-seat table, and commonly adds a "bet behind" option on other players' hands. Some live tables use H17 and 6:5 on certain seats or "lightning" variants with modified payouts — read the rules panel every time. Bonus terms usually weight blackjack at 5–10% of stake or exclude it.
Frequently asked questions
What is the house edge in blackjack?
With basic strategy at a six-deck table where the dealer stands on soft 17, doubling after splits is allowed and blackjack pays 3:2, about 0.40%. Late surrender takes it to roughly 0.33%; H17 adds 0.22%; a 6:5 payout adds 1.39%. Without strategy, typical players give up 2–4%.
Why is 6:5 blackjack bad?
A natural blackjack arrives about once every 21 hands. Being paid 1.2 times your bet instead of 1.5 times costs 0.3 units each time, which works out to about 1.39% of every hand played. That single rule more than triples the house edge of an otherwise good game. Always choose 3:2 tables.
Does the number of decks matter in blackjack?
Yes, but less than the payout and dealer rules. Going from eight decks to one reduces the house edge by about 0.48%, mainly because blackjacks and successful doubles become more likely. A single-deck game that pays 6:5, however, is worse than an eight-deck game that pays 3:2.
Can you count cards in online blackjack?
Not in RNG blackjack, which shuffles every hand. In live dealer blackjack counting is technically possible but the shoe is usually cut at around 50% penetration with eight decks, bet spreads are limited and many tables use continuous shufflers, so the practical edge is close to zero. See the strategies guide for the details.
Is live dealer blackjack better than RNG blackjack?
The house edge depends on the rules, not the format. Live tables are slower (50–70 hands an hour versus 200+), which reduces expected loss per hour at the same stake, and let you see a real shoe. RNG tables offer lower minimums and more rule choice. Check the rules panel in both cases.
What is the best blackjack variant to play?
Classic blackjack with S17, DAS, late surrender and 3:2 payouts — the Atlantic City rule set — at around 0.36% with basic strategy. Variants such as Spanish 21, Switch and Free Bet can be close if you learn their specific strategy, but played with standard strategy they cost noticeably more.