Blackjack rules — and what each one costs
Most “blackjack rules” pages stop at how the game is played. This one goes further: every common rule variation shifts the house edge by a measurable amount, and knowing those numbers is how you pick a table. The full flow of a round lives in the beginner’s guide; this page is the reference layer on top.
The fixed core
Cards 2–9 count face value, tens and faces count 10, aces count 11 or 1. Players act first with free choice; the dealer then plays a forced script — draw to 16 or less, stand on 17 or more — with no decisions and no knowledge advantage except acting last. A two-card 21 is a blackjack and beats any other 21. That asymmetry — you can bust first, but you get paid 3:2 and choose your plays — is the entire game.
Dealer soft 17: S17 vs H17
Tables either stand on all 17s (S17) or hit soft 17 (H17). H17 raises the dealer’s bust rate with an ace up from 16.7% to 20.1%, but the extra draws convert more weak 17s into 18–21 — net effect: about +0.22% house edge against you. A few correct plays flip under H17 (double 11 vs A, double soft 18 vs 2); the chart page recomputes them per rule set.
Doubling and splitting rules
Double on any two cards is standard; restricting doubles to 9–11 costs you about 0.09–0.18%. Double after split (DAS) is worth about 0.14% to the player — its absence changes several pair decisions. Resplitting to 3–4 hands is a small player gain (≈0.05–0.10%); resplitting aces, rarely allowed, adds about 0.08%. Split aces normally receive exactly one card each — and a ten on a split ace counts as 21, not blackjack.
Surrender
Late surrender (after the dealer checks for blackjack) lets you forfeit half the bet in hopeless spots and is worth about 0.08% when used correctly — which means exactly the right hands and no others: 16 vs 10 is the canonical case. “Early surrender”, before the peek, is far more valuable (≈0.6%) and essentially extinct.
Peek vs European no-hole-card
American tables deal the dealer a hole card and peek for blackjack before you act — you can’t lose a doubled or split bet to a dealer natural. European ENHC games deal no hole card until players finish: a dealer blackjack then takes your doubles and splits too, costing about +0.11% and correctly making you shier about doubling 11 vs 10 or ace.
The payout rule that towers over everything
Blackjack paying 6:5 instead of 3:2 adds about +1.39% to the house edge — four to six times the impact of any rule above. A “bad-rules” 3:2 table is almost always better than a “good-rules” 6:5 one. Check the felt before you sit.
Rule impact cheat sheet
| Rule | Effect on house edge (approx.) |
|---|---|
| Blackjack pays 6:5 instead of 3:2 | +1.39% (avoid) |
| Dealer hits soft 17 (H17) | +0.22% |
| European no-hole-card (ENHC) | +0.11% |
| No double after split | +0.14% |
| Double restricted to 10–11 only | +0.18% |
| Late surrender offered | −0.08% (helps you) |
| Resplit aces allowed | −0.08% (helps you) |
| Single deck instead of eight | −0.48% (helps you — if it’s still 3:2) |
Figures are engine-derived approximations for typical baselines; exact values shift slightly with the surrounding rule set — methodology here. Preset charts for Vegas Strip, Atlantic City, European and single-deck games, each with its computed house edge, are on the strategy chart page — or price any combination yourself with the house edge calculator.