When the dealer hits soft 17 (H17), three doubling plays and three surrender plays change in basic strategy, and the surrender ones only matter if your table offers surrender. The rule also costs you about 0.22% in expected return, so it is a worse game before you touch the chart.
This guide lists exactly which cells move, explains why each one does, and shows how much the rule costs in practice. The base chart it refers to is in the full basic strategy chart, for 4 to 8 decks.
What “hits soft 17” means
A soft hand counts an ace as 11 without busting. The dealer holds soft 17 with A,6 (or A,A,5, or A,2,4 and so on). With S17 the dealer stops there. With H17 the dealer draws, which cannot bust the dealer on that one card (an ace-6 plus any card never goes over 21) and can lift the total to 18 through 21.
The effect is a different spread of dealer results. Under H17 the dealer finishes on exactly 17 less often, and ends up on 18 to 21 more often, with some extra busts when the draw goes the other way. This only comes into play when the dealer’s hand contains an ace, which is why the changes cluster against an ace upcard and a couple of weak upcards. The shift is small in each hand, which is why only a few borderline plays flip.
The exact deviations
These are the differences from the 4 to 8 deck stand-on-soft-17 chart, with the Wizard of Odds as the reference.
| Hand | Dealer upcard | S17 play | H17 play | Notes |
|---|---|---|---|---|
| Hard 11 | Ace | Hit | Double | Applies when doubling is allowed |
| Soft 18 (A,7) | 2 | Stand | Double (otherwise stand) | Shown as “Ds” |
| Soft 19 (A,8) | 6 | Stand | Double (otherwise stand) | Shown as “Ds” |
| Hard 15 | Ace | Hit | Surrender | Only if late surrender is offered |
| Hard 17 | Ace | Stand | Surrender | Only if late surrender is offered |
| 8,8 | Ace | Split | Surrender | Only if late surrender is offered; otherwise keep splitting |
If there is no surrender at your table, only the first three rows apply. Every other cell of the chart stays the same.
What this looks like on the chart
Take the standard hard, soft and pairs grids from the main chart and change these cells:
- Hard 11 against A: from H to D.
- Soft 18 against 2: from S to Ds.
- Soft 19 against 6: from S to Ds.
- With surrender: add “Rh” to hard 15 against A, add “Rs” to hard 17 against A, and “Rs” to 8,8 against A (meaning surrender if offered, otherwise play it normally: hit 15, stand on 17, split 8s).
Why each change happens
Double 11 against an ace
Under S17, hitting 11 against an ace is a narrow call. H17 gives the dealer a slightly different spread of results, and that tips the extra bet on an 11 into positive territory compared with simply hitting. The gain from doubling is slim. That is why it only flips under H17, and why it does not flip at an S17 table.
Double soft 18 against 2, soft 19 against 6
These are borderline plays where a decent soft hand faces a vulnerable dealer card. You cannot bust a soft hand on one card, so doubling carries little risk of wrecking a good total. Under S17, standing is marginally better; under H17, doubling is marginally better. Both gaps are small. The honest reason is a calculation, not an intuition: the solver compares the average outcome of each option and the answer changes sign.
Surrender 15, 17 and 8,8 against an ace
These are the clearest signs that an H17 ace is stronger. Against a dealer ace, a hard 15, a hard 17 and a pair of 8s all lose on average, and under H17 they lose by enough that giving up half your bet beats playing on. Standing on hard 17 against an ace is already a close play under S17. A pair of 8s is the one to remember: you split it against an ace if there is no surrender, but you surrender it if surrender is available.
What H17 actually costs
The Wizard of Odds lists H17 as a change of -0.22% to the player’s return when compared with S17, other rules held constant. In dollars:
| Average bet | Hands per hour | Extra expected loss per hour |
|---|---|---|
| $10 | 60 | about $1.32 |
| $25 | 60 | about $3.30 |
| $100 | 60 | about $13.20 |
These are expected values, not what will happen in a session. Over short play your results will be dominated by variance.
Context matters. The baseline game is already about 0.33% against you with six decks, S17, double after split and late surrender. H17 adds roughly another 0.22 percentage points on top of that. It is worth having on your radar, but it is nowhere near the damage done by a 6:5 payout, which costs about 1.39%.
Does the chart change recover the cost?
No. The chart changes above are the best possible response to H17. They limit the damage, but the dealer rule still costs the player about 0.22%. Using the S17 chart at an H17 table makes the loss slightly larger, though only by a small amount since at most six cells are wrong.
So the practical lesson is that the soft 17 rule is a price tag, not a puzzle. You pay it, or you look for a table that does not charge it.
Table-selection order
If you have a choice, rank tables by the following order of impact:
- Blackjack payout. 3:2 is standard; 6:5 costs about 1.39%.
- Dealer soft 17 rule. S17 beats H17 by about 0.22%.
- Number of decks. Fewer is better for the player, by small margins.
- Double after split, resplitting, late surrender. Each is worth a tenth of a percent or so.
A 3:2, H17 table is better than a 6:5, S17 table. The payout swamps the soft 17 rule by a factor of six.
Spotting the rule at the table
The soft 17 rule is usually printed on the felt, often in small letters along the arc by the dealer’s position: “Dealer must draw to 16 and stand on all 17s” is S17, while “Dealer hits soft 17” is H17. If you cannot find it, ask the dealer before you buy in. Online, the rules panel or help page states it. Do not assume that a casino uses one rule everywhere, because it often differs between tables in the same room, and sometimes between minimum-bet levels.
It also pays to read the rest of the rule line in the same glance. A table that hits soft 17 may also pay 6:5 or limit doubling. The soft 17 rule is only one of several costs, and the combined effect is what you are paying.
Common mistakes
- Using the S17 chart without checking. The sign by the table states the rule. Look before you play.
- Doubling 11 against an ace at an S17 table. The change only applies when the dealer hits.
- Surrendering at tables that do not offer it. Surrender must be announced before you act, and many tables do not have it.
- Overpaying to avoid H17. If getting an S17 table means sitting at 6:5 or paying a much higher minimum, the cheaper-looking game may not be.
Try it yourself
Set the strategy chart tool to dealer hits soft 17 and compare the grid with the stand version. The six cells in the table above should light up as differences. Drill them in the trainer until the ace-up decisions stop needing a pause.
The edge is against you either way, so play for the entertainment you are paying for and keep to a limit you set in advance.
Related guides
- Are strategy cards allowed at the table?: etiquette and the rules for using a card at a live table.
- Where the blackjack house edge comes from: why the casino has an edge at all and how rules move it.
- Single deck blackjack strategy: how one deck shifts the chart, and why 6:5 payouts cancel the benefit.