Blackjack Rule Variations: Which Variants Use Which Rules

Each row is one rule that changes between the games. Each column is one game, ordered from the lowest house edge to the highest. Cells ringed in purple differ from the comparison rules, which are six decks, the dealer hitting soft 17, doubling after a split and a natural paying 3 to 2. Turn the ring off with the switch above the table if you prefer a plain grid, or use the menu to show a single rule.

Green text marks a setting that helps the player against the comparison rules, and pink text marks one that hurts. Neither colour is a verdict on the game: a rule that helps in one row may be paid for in another. Spanish 21 is the clearest case. It removes the four tens from every deck, which costs the player, and it makes up part of that with a player 21 that always wins, bonus payouts, late surrender and double down rescue.

The last row is the house edge: the average loss per round as a share of the starting bet, for a player who follows the correct strategy for that rule set. The figure is an average over many rounds, not a prediction for one session. Rules a game shares with every other column are left out of the grid, so the matrix only shows where the games disagree.

The house edge in the last row is not the sum of the costs printed under the rules. Rules interact, so each cost is measured from the comparison rules and a different starting point gives a slightly different change. The calculator on the house edge page prices any combination you choose.

The rules do not all matter equally. Measured against the comparison rules at 0.62%, one change at a time, the effect on the house edge looks like this. A cost is a rise in the edge and a saving is a fall, in percentage points of the starting bet.

Two things stand out. First, the natural payout is far ahead of everything else. A 6 to 5 payout costs 1.36 points, more than a single deck, the soft 17 rule, surrender and double after split put together, and no favourable rule wins it back. Second, the small rules are small. Splitting to three hands instead of four moves the edge by only 0.01 points, and the whole table of favourable rules adds up slowly.

Two rules on the list are missing from the grid because the calculation does not cover them. Early surrender and games with no hole card are outside the modelled set, so their cost is not printed here. European Blackjack and Double Exposure have their own figures on their own pages.

Some rows of the matrix are about the shape of the round rather than a price you can quote as a single number.

Dealer cards. Most tables deal the dealer a hole card and check for a natural before you act, so a dealer natural ends the round at once. European Blackjack deals no hole card, and the dealer draws the second card only after every player has finished, which raises what a doubled or split hand can lose to a dealer natural. In Double Exposure both dealer cards are face up. In Pontoon the dealer starts with one card.

Dealer 22. In Free Bet Blackjack and Blackjack Switch, a dealer who reaches exactly 22 pushes against most player hands that have not already busted, instead of busting. It removes the dealer's most common way to lose, and the games pay for it with other perks: free doubles and splits in the first, and a swap of the second cards in the second.

Ties. Ordinary blackjack pushes a tie. Double Exposure hands ties to the dealer and pays a natural at even money, one to one.

Tens removed. Spanish 21 and Pontoon play with 48-card decks that have no ten-spot cards. Face cards remain and still count ten. Fewer tens means fewer strong totals for the player, and the bonus payouts and the player 21 that always wins are the rules that pay part of that back.

Bonus payouts. Spanish 21 pays extra for a 21 made with five or more cards, and for special hands such as 6-7-8 and 7-7-7. Pontoon has its own bonus hands. These payouts are listed in the game rules and are part of the house edge figures for the games that have them.

A rule set is not one thing. In New Jersey the regulator fixes the shape of the game and leaves a short list of choices to the casino, such as the soft 17 rule. On the Las Vegas Strip the documents publish no shared rule set, and each casino fills in its own. That is why the matrix shows one setting per game, while the rule documents themselves show ranges: Spanish 21 is documented with the dealer both standing and hitting on soft 17, and its house edge is 0.41% (Spanish 21, dealer stands on soft 17. House edge per starting bet: the average loss per round as a share of the bet placed before the cards are dealt, doubles and splits included in the result. Rules: 6 decks of 48 cards (the ten-spot cards removed), dealer stands on soft 17, dealer checks for blackjack with a hole card, blackjack pays 3:2, double on any number of cards, double after split, split up to 4 hands, aces may be resplit, split aces may be hit, late surrender, a doubled bet may be rescued, a player 21 beats a dealer 21, bonus payouts: 5-card 21 pays 3:2, 6-card 21 pays 2:1, 7-or-more-card 21 pays 3:1, 6-7-8 mixed pays 3:2, 6-7-8 suited pays 2:1, 6-7-8 in spades pays 3:1, 7-7-7 mixed pays 3:2, 7-7-7 suited pays 2:1, 7-7-7 in spades pays 3:1, bonuses are not paid on split hands. The player follows the printed strategy chart for these rules from a full shoe, and never takes insurance or even money.) in one case and 0.81% (Spanish 21, dealer hits soft 17. House edge per starting bet: the average loss per round as a share of the bet placed before the cards are dealt, doubles and splits included in the result. Rules: 6 decks of 48 cards (the ten-spot cards removed), dealer hits soft 17, dealer checks for blackjack with a hole card, blackjack pays 3:2, double on any number of cards, double after split, split up to 4 hands, aces may be resplit, split aces may be hit, late surrender, a doubled bet may be rescued, a player 21 beats a dealer 21, bonus payouts: 5-card 21 pays 3:2, 6-card 21 pays 2:1, 7-or-more-card 21 pays 3:1, 6-7-8 mixed pays 3:2, 6-7-8 suited pays 2:1, 6-7-8 in spades pays 3:1, 7-7-7 mixed pays 3:2, 7-7-7 suited pays 2:1, 7-7-7 in spades pays 3:1, bonuses are not paid on split hands. The player follows the printed strategy chart for these rules from a full shoe, and never takes insurance or even money.) in the other.

The reference rule for each column is the one this site can back with a regulator document, and the second figure is shown on the game's own page where a documented choice exists. When the felt at a real table differs from the column, the column is a guide and the felt is the rule. The Vegas and Atlantic City page shows this at work: one city publishes a single rule set, the other publishes none.

Read the felt and the rules card before you play. The order below puts the rules by their weight in the house edge table above.

1. What does a natural pay? If the felt says 6 to 5, the game is a different bet from 3 to 2 blackjack, whatever else it offers.
2. Does the dealer stand or hit on soft 17? The felt usually prints it.
3. How many decks are in the shoe, and is doubling allowed after a split?
4. Is surrender offered, and against which dealer cards?
5. Is there a dealer 22 push, no hole card or a tens-removed deck? Those change the game, not just its price.

If a rule is not printed, ask the dealer. The rules of a table are public, and a player who does not know them cannot use the correct strategy for them. This page is for information only. Use play money to practise and play within limits you can afford.