Blackjack Switch: The Price of Swapping

Updated 25 August 2026

You play two hands, and you may swap the second card of one for the second card of the other. It sounds like a gift, and it is an enormous one — we computed it at 9.29 percentage points. The casino takes almost all of it back with two of the harshest rules in the building.

What the casino charges you

Blackjack Switch does not simply hand you a swap. It rewrites two rules first, and both are worse than anything you will meet at a normal table.

Both figures are our own. The second one is worth checking by hand, because it is the kind of number that ought to be checkable: you are dealt a blackjack 4.75% of the time, you now collect 0.3 of a bet less when it happens, and you only get paid at all when the dealer does not have one too. That comes to 2.27%, and our engine returns 2.266%.

The dealer breaks with 22 more often than with any other total, because 22 is what comes out of every stiff hand plus a ten. That is exactly why this rule was chosen: it takes the most common piece of good news away from you. The full breakdown is in how often the dealer breaks.

What the swap is worth

Here is the measurement that makes the game make sense. We ran the identical rule set twice — same decks, same soft-17 rule, dealer still pushing on 22, blackjack still paying even money — once with the swap and once without it.

Nine point three points. Nothing else in a casino hands a player that much and then charges for it. It also tells you something blunt: in this game the swap decision is not a flourish, it is the entire edge. Get it wrong often enough and you are playing a 9.84% game.

How the decision actually goes

Every number below is the expected value of the whole round — both hands together, in units of one bet, so the range runs from −2 to +2. The dealer upcard is fixed in each row.

The first row is the one everybody sees: 16 and 15 become 20 and 11, and the round swings by more than a bet and a half.

The third row is the one that costs people money. Swapping A-10 with 10-10 gives you back the same two hands — an ace with a ten, and two tens. Nothing changed except that a blackjack you switch into is not a blackjack any more, it is a plain 21. That rule alone is the entire 0.196 difference in that row.

The last row is worth remembering for the opposite reason. When your two second cards are the same rank, swapping is not a decision at all — you end up holding the identical pair of hands. No amount of staring will help.

Our number against the published one

We compute 0.5424% for six decks against a published 0.58%, and 0.5861% for eight decks. The gap of about four hundredths runs the same way in every variant we model in full, and it has a mundane cause: published figures come from simulations that deal from a shoe with a cut card and follow a strategy chart, while our engine works out the exact composition of the shoe and plays the best available move. The cut card alone is worth 0.020% by Wizard of Odds’ own measurement; correct play accounts for the rest.

In other words our figure is the floor and the published figure is what a good chart player actually pays. Use 0.58% to plan around.

Is it a good game?

At around 0.55% it is better than most six-deck blackjack. But that assumes you make the swap decision correctly every time, and the decision is genuinely hard: you are comparing two whole two-hand outcomes, not looking up a total on a chart.

There is a second catch that matters more than it looks. Because blackjack pays even money, the reward for a good count shrinks — a large part of what a counter earns at a normal table comes from being paid 3:2 more often when the shoe is rich. That is the same reason we are hard on 6:5 tables, and here the payout is pushed lower still.

So: a good game to play, a poor game to beat.

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By Martin Kosek · every number on this site is computed by us, not copied.