H17 vs S17: What Actually Changes
One line on the felt — “dealer hits soft 17” vs “dealer stands on all 17s” — is worth about 0.22% of house edge and flips a handful of basic strategy cells. This page shows both, computed by the same engine that grades your play in the free blackjack trainer. The full charts live at the basic strategy chart (H17) and in the interactive chart for any rule mix.
What the rule means
A soft 17 is A,6 (or any ace-counting-as-11 total of 17). Under S17 the dealer stands on it and keeps a mediocre 17. Under H17 the dealer draws again — sometimes busting, but more often improving to 18–21. The redraws help the house more than the busts help you, so H17 costs the player about 0.22%: at the standard 6-deck game, +0.32% under S17 becomes +0.54% under H17. Between two otherwise-identical tables, always sit at the S17 game.
Every basic strategy cell that changes
Going from S17 to H17, these 5 cells flip (6 decks, DAS, late surrender). The theme: with the dealer's soft 17 now able to improve, you punish the ace harder and defend harder against it — the 11 vs A and A,8 vs 6 doubles appear, 15 vs A picks up the surrender, and even 8,8 vs A stops splitting and surrenders. Everything else on the chart is identical under both rules.
| Your hand | Dealer shows | S17 play | H17 play |
|---|---|---|---|
| Hard 11 | A | H | D |
| Hard 15 | A | H | R |
| Soft A,7 | 2 | S | D |
| Soft A,8 | 6 | S | D |
| Pair 8,8 | A | P | R |
It moves the count indexes too
If you count cards, H17/S17 also shifts several Hi-Lo deviation indexes — the deviation chart prints the H17 and S17 index columns side by side, and its “what changes under S17” table lists exactly which indexes move.
H17 vs S17 questions
How do I tell which rule a table uses?
It's printed on the felt, usually in the arc in front of the dealer: “Dealer must hit soft 17” (H17) or “Dealer must stand on all 17s” (S17). No felt text? Ask the dealer — it's a normal question.
Which is more common?
H17 has been spreading for two decades and now covers most US tables, especially at lower stakes — that's why the main chart here defaults to H17. S17 survives mostly at higher-limit tables and in Atlantic City-style 8-deck games like the 8-deck chart.
Is S17 worth switching casinos for?
At 0.22% it's worth switching tables, certainly — on a $25 game at 80 hands an hour it's roughly $4–5/hour saved for zero effort. Weigh a whole rule package, not just this rule, with the house edge calculator.