Blackjack Switch: rules, edge and switching strategy

Blackjack Switch deals you two hands and lets you swap their second cards, so a 10-6 and a 5-10 can become a 10-10 and a 5-6. That privilege is paid for by two rules: a dealer 22 pushes against every player hand of 21 or less, and a natural blackjack pays even money. Under six-deck Las Vegas rules with the dealer hitting soft 17, Wizard of Odds puts the house edge at 0.58% with optimal play, which makes it competitive with ordinary blackjack for a player who switches well.

Origin

Geoff Hall, a former card counter, devised the game after one too many sessions of being dealt two weak hands that would have been one strong one. Wikipedia records that he first showed it at the G2E trade show in Las Vegas in October 2000 and that it was patented in 2009. The push-22 rule he introduced to balance it has since been reused in other games, including Free Bet Blackjack.

The rules

Wizard of Odds’ description of the standard game:

Cards are dealt face up. You decide on the switch before any other action and then play each hand in turn, hitting, standing, doubling or splitting as normal. A “Russian rules” version seen in some markets adds early surrender, no hole card and S17; Wizard of Odds puts that version at 0.20%.

What the compensating rules cost

The two balancing rules are expensive in isolation. Wizard of Odds’ rule-variations table, measured in ordinary blackjack, values “dealer bust on 22 is a push” at 6.91 points to the house and “blackjacks pay 1 to 1” at 2.27 points. A game that imposed both without any compensation would carry a house edge above 9%; the switch option and the normal doubling and splitting rules bring it back to below 1%.

That is why Blackjack Switch has to be played as Blackjack Switch and not as two hands of blackjack. The push-22 rule changes the value of standing on stiff totals: when the dealer draws out to 22, a player who stood on 16 pushes instead of winning, which removes a significant part of the payoff for standing. In consequence the hitting thresholds are more aggressive than in blackjack; the most quoted example, which Wizard of Odds addresses in its reader questions, is hitting a hard 12 where a blackjack player would stand. Wizard of Odds’ basic strategy charts for the game, organised by soft-17 rule, carry those changes.

House edge by rule set

Wizard of Odds’ figures, relative to its base case of six decks, dealer hits soft 17, switched blackjack counts as 21, optimal strategy:

So a six-deck S17 game is about 0.28%, and Wikipedia cites Arnold Snyder’s estimate of 0.25% under his chosen rule set. These numbers assume optimal switching and optimal play of the resulting hands. Both are harder than blackjack basic strategy, and the gap between a typical player and optimal play is part of the casino’s return; Wizard of Odds’ reader correspondence attributes the game’s profitability to player error rather than to the rules.

The optional Super Match side bet, which pays on pairs, three of a kind and so on among your initial four cards, carries a house edge of 2.55%. A Push 22 side bet paying 11:1 on the dealer making 22 has an expected return of −11.8% under six-deck H17 rules. Neither improves the game.

How to decide a switch

The switching decision is the whole skill of the game. Optimal switching requires comparing the expected value of the two possible pairs of hands against the upcard, which no one does at the table. Published simplified strategies get close.

Cindy Liu’s simple strategy (cost about 0.17 points against optimal, an error roughly every 18.6 hands) ranks target hands from strongest to weakest:

1. 21
2. 20
3. 19
4. A-A (to split)
5. 11
6. 10
7. 9
8. 18 or 8
9. 8-8 against a dealer 2 through 8

Against a dealer 7 or 8, balance the two hands rather than concentrating strength in one. Against every other upcard, make the strongest hand you can from the list, letting the other hand fall where it may. If neither arrangement reaches a listed hand, fall back on making a 7 or 17, a pair worth splitting, a 12, or a 13, in that order, and keep aces together in a few specified cases.

Cindy Liu’s advanced strategy (cost about 0.08 points, an error roughly every 24.5 hands) assigns point values to each hand against each upcard from a table and sums the two hands under both arrangements; the higher total wins, with the simple strategy as tiebreaker. Arnold Snyder’s strategy in The Big Book of Blackjack is described as easy and intuitive and costs about 0.2 points by Liu’s measurement.

A worked example under the simple strategy: you are dealt 10-6 and 5-10 against a dealer 9. Unswitched you hold 16 and 15, two poor hands. Switched you hold 10-10 (20) and 5-6 (11), the second and fifth entries in the ranking. Switch. Against a dealer 7 the answer is the same here because 20 and 11 are both excellent; the balancing rule applies when one arrangement produces a very strong and a very weak hand while the other produces two moderate ones.

Playing the hands after the switch

Once switched, each hand is played with the game’s own basic strategy, not the blackjack chart. The main differences are driven by push-22: hit more stiff hands against low upcards, and treat a natural as an even-money hand rather than a premium one. The site’s trainer and strategy chart cover conventional six-deck S17 blackjack only; use them to master the base game before adding the switch layer.

Blackjack World Tour is a free iOS blackjack game played with virtual chips; it is a social casino with in-app purchases and no real-money gambling. Blackjack Switch in a live casino is a real-money game whose low published edge depends on switching decisions most players make imperfectly.

Related reading

• Free Bet Blackjack
• How rule variations change the house edge
• Double exposure and other variants
• Basic strategy