Every blackjack variant makes the same kind of offer. Something appealing goes on display: free doubles, a peek at both dealer cards, the right to swap cards between hands, bonus payouts for long hands. And somewhere in the smaller print, something quieter comes back: a payout cut, a tie that now loses, a dealer total that stops busting. The display item gets a variant named. The quiet item pays for it.
That structure is worth more than any list of variants, because it is a reading skill: a player who can find the giveback rule can price any new variant, and a player who cannot will keep judging games by their most attractive line. This article compares six variants this site has covered in depth, states each trade as its own article states it, and quotes a house edge only where the source gives one.
One warning before the table, and it matters: the figures below come from different rule assumptions. The Spanish 21 number assumes a dealer who stands on soft 17; the Switch and Free Bet figures both assume six decks with a dealer who hits soft 17 but come from different games; the Charlie and European figures price one rule, not a whole game. They are honest numbers that cannot be lined up into a ranking. Compare the trades, not the decimals.
Six variants at a glance
| Variant | What the player gets | What the house takes back | Published figure |
|---|---|---|---|
| Spanish 21 | 21 always wins, player blackjack always wins, bonus payouts, doubling on any number of cards | The four tens removed from every deck | About 0.4 percent house edge with correct strategy, dealer stands on soft 17, commonly published |
| Double Exposure | Both dealer cards face up | Dealer wins all ties except tied blackjacks, blackjack pays even money, splits typically once | None: rules vary by property, so no single figure |
| Free Bet Blackjack | House-funded doubles on 9, 10 and 11, free splits of almost all pairs | A dealer 22 pushes instead of busting | 1.04 percent per Wizard of Odds under the standard rules it describes |
| Blackjack Switch | Swap the second card between two hands | Blackjack pays even money, and a dealer 22 pushes | 0.58 percent per Wizard of Odds, six decks, dealer hits soft 17, optimal play |
| Charlie rules | Automatic win at five to seven cards without busting | Rarely offered without offsets; 6:5 alone nearly cancels a five-card Charlie | Worth about 1.46, 0.16 and 0.01 percentage points to the player at five, six and seven cards, as Wizard of Odds calculates |
| European no hole card | The traditional one-card deal, usually paired with standing on soft 17 and a 3:2 payout | A late dealer blackjack can take doubles and split bets too | Costs about 0.11 percentage points versus an otherwise identical hole-card game, per the commonly published tables |
Spanish 21: the tens are the price
Spanish 21 is the most radical of the trades because it reaches into the deck. Each deck loses its four tens, leaving twelve ten-value cards where blackjack has sixteen, and that alone is commonly estimated to hand the house roughly two percentage points: blackjacks arrive less often, doubles land worse, and the dealer busts less on forced draws. The apology is a rule package no ordinary table offers. A player 21 always wins rather than pushing, a player blackjack always beats a dealer blackjack and still pays 3:2, doubling on any number of cards is allowed, and bonus payouts for hands like a 6-7-8 or a five-or-more-card 21, up to 3:1 on the most demanding versions, need no side bet.
Add it up with correct Spanish 21 strategy at a table where the dealer stands on soft 17 and the house edge is commonly published at around 0.4 percent, competitive with a good standard game. The catch is entirely in that qualifier: a player who carries a standard blackjack chart to this table plays a systematically wrong game, because the thin ten density and the bonus structure change many decisions.
The dealer 22 family: Free Bet and Blackjack Switch
Free Bet Blackjack states its offer in the name. On a two-card hard 9, 10 or 11, the house funds the double with a marker that pays like real money when the hand wins and costs only the original bet when it loses. Splits work the same way for every pair except ten-value pairs. The funding comes from one rule: a dealer who finishes on exactly 22 does not bust, and every remaining player hand pushes instead of winning, except a player blackjack. Under the standard rules the game's analysis describes, Wizard of Odds puts the house edge at 1.04 percent with correct play. Our article on the game notes that part of its gap from a liberal standard game comes from the dealer hitting soft 17, not from the 22 rule.
Blackjack Switch makes the most generous-sounding offer of all: two hands and the right to exchange their second cards after the deal. It pays for that twice. A player blackjack pays even money rather than 3:2, and the same dealer 22 push applies. Under the standard Las Vegas rules Wizard of Odds analyzes, six decks with the dealer hitting soft 17, optimal play carries a house edge of 0.58 percent, where optimal means the switch decisions and the variant's own chart are both played correctly. Both games rewrite the value of standing on weak hands, since some of the dealer breaks a player waits for become pushes, so a standard chart does not transfer to either.
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Double Exposure, Charlie rules and the European game
Double Exposure deals both dealer cards face up, deleting the inference problem that defines standard blackjack, and charges an unusually visible price: the dealer wins all ties except tied blackjacks, and a player blackjack pays even money. It is also the one variant here that refuses to come with a number. Because the further rules vary by property, our article on it declines to quote a single edge figure, and this comparison respects that and gives none.
Charlie rules reward length instead of total: reach five, six or seven cards without busting and the hand wins automatically. As Wizard of Odds calculates, the value falls off a cliff with each extra card, about 1.46 percentage points of house edge at five cards, 0.16 at six, 0.01 at seven, and a five-card Charlie on paper outweighs the roughly half a percent edge of a liberal standard game. That is why it is rarely offered without offsets: a 6:5 payout alone, at roughly 1.4 points, nearly cancels it.
The European no hole card game makes the quietest trade of the six. The dealer takes one card and receives the second only after the players act, so a late dealer blackjack can sweep doubles and split bets that an American peek would have protected. Full ENHC costs about 0.11 percentage points per the commonly published tables, concentrated in hands that commit extra money against a ten or an ace, and the strategy changes that follow are the game's own charts to make.
How to read any variant
The habit that generalizes is a three-step inspection. Find the giveback rule first: identify the visible perk, then hunt the quiet charge that funds it, a removed card, a pushed dealer 22, a tie that loses, a late blackjack. Check the blackjack payout second, because among the standard game's rules that line outweighs every other; our guides to payout variants and 3:2 versus 6:5 cover the ladder down to even money, and both Switch and Double Exposure charge on it. Third, assume the standard chart is wrong until a chart computed for the variant says otherwise.
None of these figures stack across variants. What transfers is the method, and the standard game is where it lives: the same rule-stacking reasoning our house edge calculator guide teaches for ordinary blackjack is what judging a variant's trade requires. 21 Trainer covers standard blackjack, with full rule customization across deck count, soft 17, double after split, surrender, split limits and the 3:2 or 6:5 payout, plus 9 casino presets, one of them a European no hole card game. It has no Spanish 21, Double Exposure, Free Bet or Switch mode: learning exactly how the standard rules interact is the skill every variant bends.
Frequently asked questions
Which blackjack variant has the lowest house edge?
There is no honest single ranking, because the published figures were computed under different rule assumptions. Spanish 21 is commonly published near 0.4 percent with correct variant strategy and a dealer who stands on soft 17, and Blackjack Switch at 0.58 percent per Wizard of Odds for six decks with the dealer hitting soft 17 and optimal play. Each number belongs to its own rule set, so compare the trades, not the decimals.
Can you use normal basic strategy in blackjack variants?
No, and each variant breaks the chart for its own reason. Spanish 21 thins the tens and adds bonus payouts, Double Exposure removes the hidden card, and Free Bet and Switch change what a dealer bust is worth through the 22 push rule. Every one of these games needs strategy computed for its own rules, and a standard chart carried over makes wrong decisions wherever the variant changed the math.
What is the dealer 22 rule in blackjack variants?
In Free Bet Blackjack and Blackjack Switch, a dealer who finishes with exactly 22 does not bust: every remaining player hand pushes instead of winning, with a player blackjack as the lone exception. The rule converts a slice of outcomes that used to be player wins into pushes, and that slice pays for the free bets in one game and, together with even money blackjacks, for the card switch in the other.
Why do blackjack variants offer players extra rules?
Because the extras are purchases, not gifts. Spanish 21 hands out bonus payouts to apologize for removing the tens, Double Exposure shows both dealer cards and charges for it in ties and payouts, and Free Bet funds doubled bets and splits with the dealer 22 push. Reading a variant means finding the quiet rule that pays for the loud one, then judging whether the trade is worth it.
Does 21 Trainer teach these blackjack variants?
Only the European no hole card rule, which is one of its 9 casino presets. Otherwise the app teaches standard blackjack, with full rule customization including deck count, soft 17, double after split, surrender, split limits and a 3:2 or 6:5 payout, and charts that redraw for the selected rules. It has no modes for Spanish 21, Double Exposure, Free Bet or Switch. Learning how standard rules stack is what makes any variant easier to evaluate.