Blackjack House Edge, Measured
Every number on this page comes from our own simulations: 20,000,000 hands per configuration, played with mathematically perfect basic strategy through the same engine that powers our trainer and free play table. House edge is the percentage of each initial bet the casino keeps in the long run. At 0.5%, a $25-a-hand player loses about $12 per hundred hands.
Baseline table
6 decks · H17 · DAS · 3:2
0.66%
house edge with perfect basic strategy
Number of decks
Fewer decks favor the player, mostly through more frequent blackjacks and better doubles.
| Configuration | House edge | vs baseline | |
|---|---|---|---|
| 1 deck | 0.15% | −0.50pp | |
| 2 decks | 0.44% | −0.22pp | |
| 4 decks | 0.58% | −0.07pp | |
| 8 decks | 0.68% | +0.03pp |
Rule variations
Each measured against the baseline with only that rule changed.
| Configuration | House edge | vs baseline | |
|---|---|---|---|
| Dealer stands on soft 17 (S17) | 0.47% | −0.19pp | |
| No double after split | 0.79% | +0.14pp | |
| Late surrender allowed | 0.59% | −0.07pp | |
| Resplit aces allowed | 0.58% | −0.07pp |
Blackjack payout
The single most expensive sign on the table: 6:5 blackjack.
| Configuration | House edge | vs baseline | |
|---|---|---|---|
| Blackjack pays 6:5 | 2.01% | +1.36pp | |
| No DAS · 6:5 (a bad table) | 2.15% | +1.50pp |
What matters most
Two things dwarf everything else. First, 6:5 blackjack payouts. They add about 1.36 percentage points, roughly quadrupling the baseline edge. Never play 6:5. Second, your own mistakes. Average players give away 1–2 percentage points to imperfect strategy, far more than any rule variation. The rules cost you half a percent. Guessing costs you triple that. That second edge is the one you can remove, so train it away for free.
Methodology
Each configuration: 20,000,000 rounds played with total-dependent basic strategy generated by our expected-value engine for that exact rule set, six-deck shoes dealt to 75% penetration (fresh rules use their own deck counts), dealer peek, no card counting, insurance always declined. Seeds are deterministic, so rerunning the simulation reproduces these numbers exactly. Statistical precision at this sample size is about ±0.05pp (two standard errors). Edge is expressed per initial bet. No number on this page is copied from another source.
Blackjack is beatable in the long run only with advantage play. For everyone else the edge above is the price of the game. Play with money you can afford to lose. Data generated 2026-08-05.