Single and double deck Blackjack game strategies: An in-depth overview

Blackjack was played with only a single deck of card in the early stages of casino playing. In single-deck games, it was easier to know how many higher-value cards stayed in the deck by card counting.

Single and double deck Blackjack game strategies: An in-depth overview

But then casinos started to include more and more card decks over the years. Then automatic shufflers were introduced by both land-based and online casinos which randomised the cards blindly making it more difficult for card counters to figure out what’s going to pop out. With too many decks in the shoe, the house edge was still marginally higher. Players were more prone to bust (go above 21 with their hand) and risk more long-term.

Currently, the rules of single-deck and multi-deck Blackjack are the same in all forms of online Blackjack: All the players get two cards each and the dealer also gets two cards but one with face-up and another with face-down. Then players have to determine whether to obtain more cards (hit) and attempt to achieve 21 without passing over. The player should stand as well (receive no further cards). The dealer takes cards once the player has their chance or turn. The side nearest to 21 wins—without going over. A Blackjack pays out at 3:2 in all ways, although there are some 6:5 payout single-deck Blackjack versions.

Single-deck basic strategy, S17

The following table shows a simple S17 single-deck game strategy.

  • Doubling down is permitted on any two cards.
  • Doubling down after splitting is permitted on any two cards.
  • The Dealer peeks.
  • The casino’s approximate disadvantage is -0.15%.
Player’s handDealer’s up-card
23456789TAce
Hard hand totals
5HHHHHHHHHH
6HHHHHHHHHH
7HHHHHHHHHH
8HHHDDHHHHH
9DDDDDHHHHH
10DDDDDDDDHH
11DDDDDDDDDD
12HHSSSHHHHH
13SSSSSHHHHH
14SSSSSHHHHH
15SSSSSHHHHH
16SSSSSHHHHH
17SSSSSSSSSS
Soft hand totals
A-2HHDDDHHHHH
A-3HHDDDHHHHH
A-4HHDDDHHHHH
A-5HHDDDHHHHH
A-6DDDDDHHHHH
A-7SD/SD/SD/SD/SSSHHS
A-8SSSSD/SSSSSS
A-9SSSSSSSSSS
Pairs
2-2SP/HSPSPSPSPSPHHHH
3-3SP/HSP/HSPSPSPSPSP/HHHH
4-4HHSP/HSP/DSP/DHHHHH
5-5DDDDDDDDHH
6-6SPSPSPSPSPSP/HHHHH
7-7SPSPSPSPSPSPSP/HHSH
8-8SPSPSPSPSPSPSPSPSPSP
9-9SPSPSPSPSPSSPSPSS
10-10SSSSSSSSSS
Ace-AceSPSPSPSPSPSPSPSPSPSP

The abbreviations stand for:

  • S – Stand
  • H – Hit
  • SP – Split
  • D – Double down (Hit, if not permitted)
  • SP/H – Split if double down after splitting is permitted (Hit, if not permitted)
  • D/S – double down (Stand, if not permitted)

 Basic Strategy for single-deck games, H17

The following table shows simple strategies for single-deck H17 gameplay.

  • Doubling down is permitted on any two cards.
  • Doubling down after splitting (DAS) is permitted on any two cards.
  • Dealer’s peeks.
  • The casino’s approximate advantage is 0.04%.
Player’s handDealer’s up-card
23456789TAce
Hard hand totals
5HHHHHHHHHH
6HHHHHHHHHH
7HHHHHHHHHH
8HHHDDHHHHH
9DDDDDHHHHH
10DDDDDDDDHH
11DDDDDDDDDD
12HHSSSHHHHH
13SSSSSHHHHH
14SSSSSHHHHH
15SSSSSHHHHH
16SSSSSHHHHH
17SSSSSSSSSS
Soft hand totals
A-2HHDDDHHHHH
A-3HHDDDHHHHH
A-4HHDDDHHHHH
A-5HHDDDHHHHH
A-6DDDDDHHHHH
A-7SD/SD/SD/SD/SSSHHH
A-8SSSSD/SSSSSS
A-9SSSSSSSSSS
Pairs
2-2SP/HSPSPSPSPSPHHHH
3-3SP/HSP/HSPSPSPSPSP/HHHH
4-4HHSP/HSP/DSP/DHHHHH
5-5DDDDDDDDHH
6-6SPSPSPSPSPSP/HHHHH
7-7SPSPSPSPSPSPSP/HHSH
8-8SPSPSPSPSPSPSPSPSPSP
9-9SPSPSPSPSPSSPSPSS
10-10SSSSSSSSSS
Ace-AceSPSPSPSPSPSPSPSPSPSP

The abbreviations stand for:

  • S – Stand
  • H – Hit
  • SP – Split
  • D – Double down (Hit, if not permitted)
  • SP/H – Split if double down after splitting is permitted (Hit, if not permitted)
  • D/S – Double down (Stand, if not permitted)

Basic double-deck blackjack strategy, S17

The following table shows the simple S17 double-deck games technique.

  • Doubling down is permitted on any two cards.
  • After splitting, doubling down is permitted and there is no surrender.
  • Dealer’s peeks.
  • The house’s approximate advantage is 0.20%.
Player’s hand                                                                                                                 Dealer’s up-card
23456789TAce
                                                                                                          Hard hand totals
5HHHHHHHHHH
6HHHHHHHHHH
7HHHHHHHHHH
8HHHHHHHHHH
9DDDDDHHHHH
10DDDDDDDDHH
11DDDDDDDDDD
12HHSSSHHHHH
13SSSSSHHHHH
14SSSSSHHHHH
15SSSSSHHHHH
16SSSSSHHHHH
17SSSSSSSSSS
                                                                                                    Soft hand totals
A-2HHHDDHHHHH
A-3HHHDDHHHHH
A-4HHDDDHHHHH
A-5HHDDDHHHHH
A-6HDDDDHHHHH
A-7SD/SD/SD/SD/SSSHHH
A-8SSSSSSSSSS
A-9SSSSSSSSSS
                                                        Pairs
2-2SP/HSP/HSPSPSPSPHHHH
3-3SP/HSP/HSPSPSPSPHHHH
4-4HHHSP/HSP/HHHHHH
5-5DDDDDDDDHH
6-6SPSPSPSPSPSP/HHHHH
7-7SPSPSPSPSPSPSP/HHSH
8-8SPSPSPSPSPSPSPSPSPSP
9-9SPSPSPSPSPSSPSPSS
10-10SSSSSSSSSS
Ace-AceSPSPSPSPSPSPSPSPSPSP

The abbreviations stand for:

  • S – Stand
  • H – Hit
  • SP – Split
  • D – Double down (Hit, if not permitted)
  • SP/H – Split if double down after splitting is permitted (Hit, if not permitted)
  • D/S – Double down (Stand, if not permitted)

Basic double-deck blackjack strategy, H17

The following table shows the simple H17 double-deck game technique.

  • Doubling down is permitted on any two cards.
  • Doubling down after making a split (DAS) and no surrender.
  • Dealer’s peeks.
  • The casino’s approximate advantage is 0.40%.
Player’s handDealer’s up-card
23456789TAce
Hard hand totals
5HHHHHHHHHH
6HHHHHHHHHH
7HHHHHHHHHH
8HHHHHHHHHH
9DDDDDHHHHH
10DDDDDDDDHH
11DDDDDDDDDD
12HHSSSHHHHH
13SSSSSHHHHH
14SSSSSHHHHH
15SSSSSHHHHH
16SSSSSHHHHH
17SSSSSSSSSS
Soft hand totals
A-2HHHDDHHHHH
A-3HHDDDHHHHH
A-4HHDDDHHHHH
A-5HHDDDHHHHH
A-6HDDDDHHHHH
A-7D/SD/SD/SD/SD/SSSHHH
A-8SSSSD/SSSSSS
A-9SSSSSSSSSS
Pairs
2-2SP/HSP/HSPSPSPSPHHHH
3-3SP/HSP/HSPSPSPSPHHHH
4-4HHHSP/HSP/HHHHHH
5-5DDDDDDDDHH
6-6SPSPSPSPSPSP/HHHHH
7-7SPSPSPSPSPSPSP/HHSH
8-8SPSPSPSPSPSPSPSPSPSP
9-9SPSPSPSPSPSSPSPSS
10-10SSSSSSSSSS
Ace-AceSPSPSPSPSPSPSPSPSPSP

The abbreviations stand for:

  • S – Stand
  • H – Hit
  • SP – Split
  • D – Double down (Hit, if not permitted)
  • SP/H – Split if double down after splitting is permitted (Hit, if not permitted)
  • D/S – Double down (Stand, if not permitted)

The game rules tend to vary from one casino to another, but the strategies used in these tables apply to all circumstances, with very little modification. It is very convenient to make use of these tables, you have to check the worth of your hand, look at what face-up card the dealer holds and see if all conditions accept. These laws concern any number of cards held by the hand. Hard hands over 17 played as hard 17 – you can stand on them all.

Pros and of each strategy

The one-deck Blackjack benefit is that it is easier to trace the cards out of the deck. However, the house edge of the insurance bet is higher (5.9%), since fewer 10-value cards are present on the deck. Single-deck Blackjack games are getting sparse nowadays whereas Multi-deck or Double-deck Blackjack is more commonly available online and, given the higher 10s and image cards, it’s slightly easier to double down.

If you are interested in trying out these strategies and playing different variations of Blackjack you can easily find the Blackjack game of your choice at Winissimo.

Winissimo also provides the more exciting Live Blackjack version too where you can enjoy the game in a land-based casino ambience without having to visit one.

Is the house edge higher in one of the games?

The house edge in Blackjack relies on a number of factors, including the Blackjack variation you are playing and how many decks are used in the game. European blackjack, for example, gives a house edge lower than other blackjack styles.

The house edge may be diminished or raised by deck numbers. As a guideline, the lower the number of decks used in the game, the lower the casino advantage. Some players do claim that the card ratio is similar, irrespective of whether a game uses a single or seven decks.

While that may be reasonable to understand, the fact that players have more Blackjacks, good splits and favourable double-downs in single-deck games still stands. This is because the consequence of the removal of any card is more marked in games with fewer decks. The likelihood of hitting and successfully doubling a Blackjack decreases marginally with each deck added to the table.

Using the above mentioned strategies will help get the Blackjack odds in a player’s favour.