Beating Bonuses Beating Bonuses




Blackjack Switch is a blackjack variation offered at Playtech, Grand Virtual, World Gaming, and (some) DGS casinos. I find the game to be more interesting and enjoyable than traditional blackjack. When available, I usually choose blackjack switch over other games for playing through bonuses. Blackjack switch is the lowest house edge game available at all of these softwares. However, strategy is more complex than traditional blackjack due to the switch decisions.


Rules and Play

After being dealt the initial two cards in each hand, the player has the opportunity to swap the top card between the two hands. In the picture at the top of the page, the player could either keep the blackjack and 11 or swap the top card between hands and make a soft 18 and 14. In exchange for this benefit, there are additional rules that favor the dealer:

-A dealer 22 is not treated as a bust. Instead it counts as a push against all hands except for a player blackjack

-Blackjack pays 1:1

-The dealer hits on soft 17



The table below shows optimal strategy with Playtech rules (6 decks). Under Grand Virtual rules (8 decks), do not double on 9 vs 5. For switch decisions, see the Blackjack Switch Calculator.

Your Hand Dealer's Face-up Card
 2   3   4   5   6   7   8   9  10  A 
5-8 H H H H H H H H H H
9 H H H D D H H H H H
10 D D D D D D D H H H
11 D D D D D D D D H H
12 H H H S S H H H H H
13 H S S S S H H H H H
14 S S S S S H H H H H
15 S S S S S H H H H H
16 S S S S S H H H H H
17+ S S S S S S S S S S

A,2 H H H H H H H H H H
A,3 H H H H H H H H H H
A,4 H H H H H H H H H H
A,5 H H H H D H H H H H
A,6 H H H D D H H H H H
A,7 S S S Ds Ds S S H H H
A,8 S S S S S S S S S S
A,9 S S S S S S S S S S

2,2 H H H P P P H H H H
3,3 H H H P P P H H H H
4,4 H H H H H H H H H H
5,5 D D D D D D D H H H
6,6 H H P P P H H H H H
7,7 S P P P P P H H H H
8,8 P P P P P P P P H H
9,9 S S P P P S P P S S
10,10 S S S S S S S S S S
  Double if Possible, Otherwise Hit
  Double if Possible, Otherwise Stand
  Split (Pair)


House Edge

With optimal strategy, the house edge is only 0.17% with 6 decks (Playtech, World Gaming, DGS) and 0.19% with 8 decks (Grand Virtual).

To protect against card counters, most Vegas casinos have increased house edge by making a switched A/10 count as 21, rather than blackjack. This change increases house edge to ~0.6%. I am not aware of this version being used at online casinos.


Variance and Bet Size

The standard deviation of blackjack switch is complex. If you play a single hand (no switches) with blackjack switch rules including 1:1 payouts for blackjack, the standard deviation per hand is 1.06. However, switch decisions influence this standard deviation in two ways:

1. Hands that have an optimal strategy of double or split often have a high EV, so switch decisions tend to favor doubles and splits over other options. Using an imprecise infinite deck simulation, I estimate that switch decisions increase the rate of doubled bets by nearly 40%, increasing the standard deviation per hand to 1.10 and the average bet size to 1.12.

2. The correlation between multiple player hands in blackjack is ~0.365. Blackjack switch has a lower correlation between hands than standard blackjack because switch decisions often improve one hand and worsen another. I'm not certain the degree of effect. I'll assume the switch decisions decrease correlation slightly, from 0.365 to 0.30.

Using the assumptions above, I estimate a standard deviation per round of 1.25 and a standard deviation per unit wagered of 0.83. The latter value of 0.83 corresponds to the expected loss over a wagering requirement. For reference, two-handed standard blackjack has a standard deviation per round of ~1.33 and a standard deviation per unit wagered of ~0.89.

The table below shows the chance of ending above the deposit balance with unlimited bankroll, after completing a wagering requirement with 4 bet sizes (bet size per hand). See the Return & Variance Calculator for more specific estimates. Note that the calc's standard deviation and average bet size values are expressed per hand. They correspond to 1.10 and 1.12 in the discussion above.

Bet Size Playthrough Requirement
10xB 20xB 30xB 40xB 50xB 60xB 70xB 80xB
B/100 99.6% 97% 93% 90% 87% 84% 82% 80%
B/50 97% 90% 85% 81% 78% 76% 74% 72%
B/20 88% 79% 74% 71% 69% 67% 66% 64%
B/10 80% 72% 68% 65% 64% 62% 61% 60%


Copyright © 2008-2014 All Rights Reserved.