There are few more demoralising situations in a game of blackjack than deciding how to progress your hand when you are staring directly at a dealer’s upcard of an ace.
The common feeling is that the next move is immaterial whatever you do, as the dealer is almost certain to complete their blackjack when flipping their second card.
However, the probability that the dealer does have a 10 or picture card as their second card is actually marginally less than one in three.
So, although the dealer is clearly in an advantageous position by holding an ace, they are far from guaranteed to beat your hand, particularly with a perfect 21.
Critical for you is to make the right play to offer the best chance of reducing any long-term losses.
It is also important to note that the decision you make may alter slightly depending on whether the casino house rules dictate that the dealer must hit or stand on soft 17.
When to show some aggression
Regardless of whether your hand is soft or hard in its make up, the recommended play for any total up to 15 is to hit for additional cards.
Where the strategy differs is when your hand adds up to total 11 in a multi-deck game.
If the dealer is forced by house rules to stand on soft 17, the suggested move is just to take an ordinary hit.
However, if the dealer must hit on soft 17, a more aggressive move is endorsed. Rather than simply hitting, you should double down instead.
It may seem illogical to double your bet when taking on an ace, but the dealer is at a greater risk of busting under these rules.
If allowed to stand on soft 17, the dealer will complete a hand of 17 or greater 83% of the time and 19 or more almost half the time.
Should you double down and receive a two, three, four, five or six, you would be in an incredibly vulnerable position.
But the percentages tilt enough when the dealer has to hit on soft 17 to make doubling down more viable.
Another more attacking play relates to the splitting of a pair of eights. After all, in many circles one of the golden rules of blackjack is to always split aces and eights.
We’ve previously touched on why splitting eights is deemed a good play from the point of view that it means you lose less in the long run.
Meekness is not a weakness
Yet there are other occasions where it pays to take the least aggressive approach. Knowing the time to surrender when in a weak position is a productive way of limiting losses.
By throwing in the towel in a hand following the deal, when both yours and the dealer hand are incomplete, half your original bet is returned.
Not all casinos offer the opportunity to surrender, so this is even more reason to take advantage of this rarity when there is the chance.
Any hard hand totalling 16 is considered an automatic surrender.
We’ve already highlighted that the dealer will total 17 or more in 83% of hands when starting with an ace, while you’ll bust 62% of hands when hitting on 16.
These two factors combined clearly show that you are likely to bust and the dealer is not, enhancing the appeal of the surrender.
Card value considerations
Hand totals of 15 and 16 are among the more tricky to play because of the likelihood of busting. The bust-out rate when hitting on 15 is 58%.
However, consider a hand of 15 made up of an 8-7, in comparison to a 10-5.
In the first case, two cards that would bring about a bust if you hit have been taken out of the deck. With the second example, one positive and one negative card have been removed.
Therefore, this has a marginal impact on your probability of busting. Certainly, a hit with the 8-7 is slightly more attractive than with the 10-5.
What about insurance?
The opportunity to take out insurance is best considered as a side bet, considering whether the dealer will complete their blackjack or not from their initial ace.
Your cost if you wish to take out the insurance is half your initial stake and you’ll be paid out at 1/1 should the dealer get the 10 to go with their ace.
If the dealer’s second card is another value, the side bet is lost.
We have previously devoted an entire article looking into the maths behind why taking out insurance is rarely a good idea, alongside the cases where it may make sense and why insurance is less valuable if you have a stronger hand.