Last Updated: February 18, 2020
The probability of getting a blackjack (which pays off at 3 to 2), is 16/51, or 31.37%. But let's look at the same situation with 8 decks in play: You're dealt an ace. You now have 415 cards left in the shoe, and 128 of them are worth 10. The probability of getting a blackjack is 128/415, or 30.84%. Things get worse as the decks are dropped, with four decks raising the advantage to 7.08%, two decks bringing it to 8.33% and worst of all is the single deck game, which stands at a 10.86% house advantage. I have however seen a single deck blackjack game with a 4 to 1 pay table, which would drop the house edge down to 3.77%. Double deck blackjack follows standard blackjack rules for the most part. Players and dealer are still required to reach a hand total as close to 21 are possible without exceeding 21. Only two major differences occur with double deck blackjack, which includes double down only on hand total of 10 or 11 and the dealer stands on a soft 17.
At first glance, it would seem only logical that a smart player will do better at a game that uses fewer decks, but that's not always the case when you compare double-deck games with six-deck games. A lot of variables come into play, not the least of which are the rules of the games, the minimum bet size required and the amount of scrutiny the games get from casino supervisory personnel. If you do not count cards, it's very likely that you'll be better off avoiding the double-deck games out there. I know some of you may be surprised by that comment, but I make it based upon the fact that many casinos have less liberal rules on their double-deck games, yet they require higher minimum bets. As a result, the casino's overall edge may be similar to that of their six-deck game, but you'll have to bet more on every hand for the privilege of playing. Because a non-counter cannot get a long-term edge over the casino, you'll just be betting more on a consistent basis and the casino will eventually get your $$$.
Now don't get me wrong here; if the rules are the same, a game using two decks will have a lower casino edge than one that uses six-decks, yet the strategies are almost identical. If the minimum bets are the same (or are at least within your comfort level), then go with the 2-decker. That's a key point, by the way. The proper Basic Strategy for a double-deck game closely resembles that of a four- or six-deck game, much more so than a single-deck game. The few differences between a two-deck and six-deck game with the same rules (dealer hits or stands on soft 17, double after split is allowed, etc.) lie mainly in splitting pairs and, since pairs are the rarest hands you'll get, the impact is negligible. I might be wrong about this, so check, but I do believe that the only change is to split a pair of 7s against a dealer's 8 in a double-deck game. In a six-decker, you don't do that. Not a hand you're going to see everyday, either way.
There are indeed only a handful of changes in strategy between the 6-deck and the 2-deck game. In a 2-deck S17 game: Split 77v8, Split 66v7, and Double 9v2. If the game is H17, also double A3v4.
My point is that you can move back and forth between DD and 6D games and not worry that you're playing improperly, but the big question is whether or not you should. We've already covered the non-counter situation, so let's turn our attention to those of you who do count. Even in this situation, the double-deck game isn't necessarily the hands-down choice and I'll show you why as we go along.
Two Deck Blackjack Odds Explained
For whatever reason, many casinos treat their double-deck games as 'premium' games, so they have higher minimum bets, may have less liberal rules, less favorable penetration and are usually watched more closely by the 'pit critters', as we lovingly call them here. Some casinos seem to think that counters are showing up in droves at their DD games and carting off chips by the box load, but that's not necessarily the case. I know of some games that are very easy to beat, but they are few and far in-between. The reality is that beating the double-decker takes extra effort and some sharp play by the counter. But you came here for answers and I have them.
Now don't get me wrong here; if the rules are the same, a game using two decks will have a lower casino edge than one that uses six-decks, yet the strategies are almost identical. If the minimum bets are the same (or are at least within your comfort level), then go with the 2-decker. That's a key point, by the way. The proper Basic Strategy for a double-deck game closely resembles that of a four- or six-deck game, much more so than a single-deck game. The few differences between a two-deck and six-deck game with the same rules (dealer hits or stands on soft 17, double after split is allowed, etc.) lie mainly in splitting pairs and, since pairs are the rarest hands you'll get, the impact is negligible. I might be wrong about this, so check, but I do believe that the only change is to split a pair of 7s against a dealer's 8 in a double-deck game. In a six-decker, you don't do that. Not a hand you're going to see everyday, either way.
There are indeed only a handful of changes in strategy between the 6-deck and the 2-deck game. In a 2-deck S17 game: Split 77v8, Split 66v7, and Double 9v2. If the game is H17, also double A3v4.
My point is that you can move back and forth between DD and 6D games and not worry that you're playing improperly, but the big question is whether or not you should. We've already covered the non-counter situation, so let's turn our attention to those of you who do count. Even in this situation, the double-deck game isn't necessarily the hands-down choice and I'll show you why as we go along.
Two Deck Blackjack Odds Explained
For whatever reason, many casinos treat their double-deck games as 'premium' games, so they have higher minimum bets, may have less liberal rules, less favorable penetration and are usually watched more closely by the 'pit critters', as we lovingly call them here. Some casinos seem to think that counters are showing up in droves at their DD games and carting off chips by the box load, but that's not necessarily the case. I know of some games that are very easy to beat, but they are few and far in-between. The reality is that beating the double-decker takes extra effort and some sharp play by the counter. But you came here for answers and I have them.
Two Deck Blackjack Odds Blackjack
Slot machine pink panther. The primary advantage to playing a double-deck game is the volatility of the count. Unlike a 4- or 6-deck game, the running count, which is converted to the True Count (count per remaining deck) in a DD game can rise or fall quickly, but it's gone almost as fast, due to the shuffle. That's obviously good when the count is negative, but no fun at all when the count is 'up'. Things happen quickly in a DD game and the wise counter takes advantage, but it requires good skills at converting to the True Count and almost needs some ability to anticipate what's going to happen, while remembering that we never make guesses when counting.
