Should you split 8s against a dealer ace?
Split them, except in shoe games where the dealer hits soft 17 and late surrender is offered: there, surrender.
Expected result per unit bet on a 6-deck table where the dealer hits soft 17, with surrender (the common Las Vegas Strip game): Surrender −0.5000 · Split −0.5148 · Hit −0.5386.
Practice on this table in the trainerBasic strategy chart for this table
The hand
You
%20scale(0.6)'%20fill='%23D40F1B'%3e%3cpath%20d='M50%2095C21%2072%203%2055%203%2032C3%2015%2015%204%2029%204C39%204%2046%2010%2050%2019C54%2010%2061%204%2071%204C85%204%2097%2015%2097%2032C97%2055%2079%2072%2050%2095Z'/%3e%3c/g%3e%3cg%20transform='translate(106%20196)%20scale(1.26)'%20fill='%23D40F1B'%3e%3cpath%20d='M50%2095C21%2072%203%2055%203%2032C3%2015%2015%204%2029%204C39%204%2046%2010%2050%2019C54%2010%2061%204%2071%204C85%204%2097%2015%2097%2032C97%2055%2079%2072%2050%2095Z'/%3e%3c/g%3e%3c/svg%3e)
%20scale(0.6)'%20fill='%23111317'%3e%3ccircle%20cx='50'%20cy='27'%20r='21.5'/%3e%3ccircle%20cx='25.5'%20cy='57'%20r='21.5'/%3e%3ccircle%20cx='74.5'%20cy='57'%20r='21.5'/%3e%3cpath%20d='M45.5%2052C45.5%2076%2041%2089%2029%2098h42C59%2089%2054.5%2076%2054.5%2052Z'/%3e%3c/g%3e%3cg%20transform='translate(106%20196)%20scale(1.26)'%20fill='%23111317'%3e%3ccircle%20cx='50'%20cy='27'%20r='21.5'/%3e%3ccircle%20cx='25.5'%20cy='57'%20r='21.5'/%3e%3ccircle%20cx='74.5'%20cy='57'%20r='21.5'/%3e%3cpath%20d='M45.5%2052C45.5%2076%2041%2089%2029%2098h42C59%2089%2054.5%2076%2054.5%2052Z'/%3e%3c/g%3e%3c/svg%3e)
Dealer
| Play | Expected result |
|---|---|
| SurrenderBest | −0.5000 |
| Split | −0.5148 |
| Hit | −0.5386 |
| Stand | −0.5948 |
| Double | −1.0771 |
Average win or loss per unit of the original bet (−0.5000 loses half the bet on average), computed exactly from the cards left in the shoe, with perfect play afterwards. In US games the numbers are after the dealer has checked for blackjack.
Why
A pair of 8s is a hard 16, the worst total in blackjack, while a single 8 is a fair start for a hand. Against an ace every option loses money on average, and splitting usually loses the least. When the dealer hits soft 17 and you can surrender, giving up half the bet is slightly cheaper. With no hole card (European rules) a dealer blackjack takes both split bets, so hit instead.
Do the table rules change the answer?
The answer changes on 6 of the 8 tables below, highlighted.
| Table | Split | Surrender | Hit |
|---|---|---|---|
| 6 decks · H17 · DAS · surrender | −0.5148 | −0.5000 | −0.5386 |
| 6 decks · S17 · DAS · surrender | −0.3651 | −0.5000 | −0.5136 |
| 8 decks · H17 · DAS · surrender | −0.5171 | −0.5000 | −0.5395 |
| 2 decks · H17 · DAS | −0.4958 | — | −0.5313 |
| 1 deck · H17 · no DAS | −0.4802 | — | −0.5201 |
| 1 deck · S17 · no DAS | −0.3277 | — | −0.4949 |
| European: 6 decks · S17 · DAS · no hole card | −0.8871 | — | −0.6647 |
| 6 decks · H17 · DAS | −0.5148 | — | −0.5386 |
H17: the dealer hits soft 17. S17: the dealer stands on soft 17. DAS: you can double after splitting. European tables have no hole card, so the dealer only checks for blackjack after you play: those numbers include losing everything you bet to a dealer blackjack. They also allow doubling on 9 to 11 only and one split.