Should you hit soft 18 against an ace?
Hit. Against a 2 through 6 the book doubles soft 18. Against a 7 or 8 it stands, and against a 9, 10 or ace it hits.
Why
Soft 18 feels like a hand to keep. Against an ace it isn't: the dealer ends on 19 or better 50.9% of the time, after checking for blackjack, and ties your 18 another 20.7%.
Hitting can't break soft 18 on the next card, since the ace drops to 1 when it has to. A card can leave you worse off, and the book hits anyway: against an ace, standing on 18 does worse.
When the answer changes
At the app's table (six decks, the dealer hitting soft 17, double after split and late surrender) the book hits soft 18 against an ace. With a single deck and the dealer standing on soft 17, the book stands instead. Every other rule set plays it the way the app's table does.
The full basic strategy chart for six decks, dealer hits soft 17, with every other rule set a tap away.
Questions
Should you hit soft 18 against a 10?
Yes. Against a 10 the book hits soft 18. A dealer showing a 10 goes over 21 23.0% of the time, after checking for blackjack.
Does the answer ever change?
Yes. With a single deck and the dealer standing on soft 17, the book stands on soft 18 against an ace.
More hands
- Should you hit soft 18 against a 10?
- Should you hit soft 18 against a 9?
- Should you hit soft 17 against a 7?
- Should you stand on soft 18 against a 2?
- Should you double soft 19 against a 6?
- Blackjack hands, one at a time
Guides
Know the book before you sit down.
