Variations in Blackjack game rules
There are several variations to Blackjack rules.
Dealer does not check for Blackjack at the beginning (Lose only original bet)
Dealer checks for Blackjack only at the end of the round. If the dealer has Blackjack, player can lose only the original bet.
Dealer does not check for Blackjack at the beginning (Lose all bets)
Dealer checks for Blackjack only at the end of the round. If the dealer has Blackjack, player can lose all bets (doubles and splits).
Dealer takes no hole card (Lose all bets)
Dealer does not take a hole card at the beginning. If the dealer ends up with a Blackjack, player can lose all bets (doubles and splits)
Dealer peeks under A only ( Dealer 10 Up 2 card 21 is not BJ)
Dealer checks for Blackjack, before any play, only if the open card is A. If the dealer has Blackjack, the play ends immediately. If the dealer open card is 10 and the hole card turns out to be an A, it is treated as 21 and not Blackjack.
Surrender
Player can surrender cards. Player will lose half the bet.
Late surrender
Player can surrender cards only if dealer does not have a Blackjack.
Early surrender
Player can surrender cards before dealer checks for Blackjack. Player will lose only half the bet even if dealer has Blackjack.
Surrender after split
Player can surrender cards even on a split hand.
Surrender after double
Player can surrender cards even after a double.
Surrender on any number of cards
Player can surrender cards even after hitting.
No double after split
Player cannot double on a split hand.
No double on soft hand
Player cannot double on a soft hand.
Double only on 10 or 11
Player can double only if hand total is 10 or 11.
Double only on 9, 10 or 11
Player can double only if hand total is 9, 10 or 11.
Double on any number of cards
Player can double even after a hit.
Blackjack pay
Amount paid when the player has a Blackjack. Traditional Blackjack pays are 3:2. But newer Blackjack games pay only 6:5 or 1:1.
Double diamond pays 2:1
When player has a Blackjack and both the cards are diamonds, player is paid 2:1. Does not apply when dealer also has a Blackjack.
Dealer always wins Blackjack
When both player and dealer have Blackjacks, dealer wins.
Player always wins Blackjack
When both player and dealer have Blackjacks, player wins.
Dealer hits soft 17
Dealer must draw on a soft 17.
Dealer stands on all 17s
Dealer must stand on a soft 17.
Resplit Aces
When Aces are split and another Ace is drawn, player can resplit it.
Draw to split Aces
Normally when Aces are split, player gets only one additional card per hand. But with this option, player can draw more than 1 card.
5 Card 21 Pays 2:1
When player hand equals 21 with exactly 5 cards, player is paid 2:1. But 5 Card 21 loses to a dealer Blackjack.
6 Cards 20 or less wins
When player hand is 20 or less with 6 or more cards, player wins automatically, except when dealer has a Blackjack. Dealer Blackjack wins.
Player loses ties
Player loses when player and dealer have the same hand total. When both have Blackjacks, it is a push.
Baseline is 6 decks, dealer peeks under both A & 10, dealer hits soft 17, double on any first two cards, double after split permitted, no surrender, no resplit of Aces. This baseline has player edge of -0.64%. All rule variations are given relative to this.
|
Rule |
Player edge (%) |
|
12 Decks |
-0.05 |
|
8 Decks |
-0.02 |
|
4 Decks |
0.04 |
|
2 Decks |
0.16 |
|
1 Deck |
0.47 |
|
Dealer takes no hole card. Lose all bets to dealer Blackjack |
-0.11 |
|
Dealer Peeks under Ace only. 10 Up 2 card dealer 21 is not Blackjack |
0.25 |
|
Late surrender |
0.09 |
|
Late and early surrender |
0.71 |
|
Surrender after split |
0.10 |
|
Surrender after double |
0.26 |
|
Surrender on any number of cards |
0.18 |
|
No double after split |
-0.15 |
|
No double on soft hand |
-0.11 |
|
Double only on 10, 11 |
-0.19 |
|
Double only on 9, 10, 11 |
-0.11 |
|
Double on any number of cards |
0.23 |
|
Blackjack pays 3:1 |
6.79 |
|
Blackjack pays 2:1 |
2.27 |
|
Blackjack pays 6:5 |
-1.36 |
|
Blackjack pays 1:1 |
-2.27 |
|
Double Diamond Blackjack pays 2:1 |
0.14 |
|
Dealer always wins Blackjack |
-0.21 |
|
Player always wins Blackjack |
0.32 |
|
Dealer stands on all 17s |
0.21 |
|
Resplit Aces |
0.06 |
|
Draw to split Aces |
0.19 |
|
Five card 21 pays 2:1 |
0.23 |
|
6 card, 20 or less wins |
0.14 |
|
Player loses ties |
-8.80 |
To find the approximate player edge for a given set of gave rules, simply add the edges for individual rule changes from the baseline. For example, to find the player edge when dealer stands on soft 17 and draw to split Aces, add 0.21 (for dealer stands and all 17s) and 0.19 (for draw to split Aces) to -0.64. This will give player edge for the new set of rules as -0.24%.