Blackjack: Single Deck vs. Multiple Deck

If you’re new to the online and offline casino game you’ve probably barely noticed it: some Blackjack games play with more decks than others.

Take a tour of Vegas or hop online and check the rules for a couple of casinos and you’ll notice that the number of decks can differ for each table.

Question is what’s the difference? And what’s ultimately better for players, one-deck Blackjack or multi-deck? We investigate.

Single Deck
If you’ve been hanging around Vegas since the Rat Pack were headlining then you know single deck used to be the only way to play Blackjack.

Why did the old-school casinos get rid of it until today? Card counting.

MIT students know how to beat the house despite four and six decks what do you think they could do with one? Plus, even without card counting, the fewer decks you have to deal with the more the odds could skew in your favor. For example: let’s say the dealer tosses you a 4 and a 7, and his up card is an Ace. In a single-deck game, 16 of the other 49 cards in the deck are cards with a value of 10, giving you a 32.7 percent chance of drawing a 10 value on your next card. But play a six-deck game, where 96 of the remaining 309 cards are a value of 10, your chances of drawing a 10 value drops to 31.1 percent.

So why would spots like Vegas and Atlantic City re-introduce one deck Blackjack knowing this? Well, there’s a catch (isn’t there always?).

First of all instead of paying 3-to-2 odds ($15 win for a $10 bet) for natural Blackjacks single-deck tables in today’s casinos pay 6-to-5 ($12 win for a $10), which increases the house edge by 1.5 percent. Also, the dealer hits on soft 17 giving the house another .20 percent advantage for that.

You can find multi-deck games all over the place, anywhere from four to six to eight. Although there’s more cards to deal with, most pros who have experienced all Blackjack styles actually prefer multi-decks over single.

This is because, when looking real close at the rules, there’s actually more of an advantage. As we said above a natural Blackjack pays 3-to-2 instead of 6-to-5. And the house edge is only .4 or .5 percent. Better than the nearly two-percent advantage today’s single-deck version has.

The Winner
It’s pretty obvious. Unless you can find a table that gives the same rules for multi-deck Blackjack on a single-deck game (good luck finding that) stick with multiple decks. We suggest going with four decks if you have a choice, you can find that style in most online and offline casinos.