The 21+3 Blackjack Side Bet: What You Need to Know

You may see it written as 21 3 blackjack and a couple of different variations of that (like blackjack 21+3 and so on), but they all refer to the same side bet.

The objective of this guide is to let you know how to play the bet, what are the winning 3-card-poker hands, and how much you will get paid when you win.

What is 21 + 3 in Blackjack?

21 + 3 is a side bet on the game of blackjack made by the player’s first two cards, and the dealer’s up card.

The name tells you what the game is about – it’s a standard game of blackjack (the ‘21’ part of the name), and there is an additional bet that you can make which is on a 3-card poker hand (the ‘+3’ part of the name).

Simply place the additional bet in the designated betting area (the big ‘3’) close to the regular betting circle.

21 + 3 Blackjack and Perfect Pairs are owned by Galaxy Gaming, so you often see them offered together on the same table.

The Winning Poker Hands

Each casino chooses its own pay table, so often the poker hands that win may not be exactly the same as in other casinos.  Here are some winning hands that were often found on the early versions of the game.

Straight Flush

All the cards are consecutive and all are of the same suit.  Like this 7, 8, and 9 of Clubs.

3-of-a-kind

All cards must be of the same numeric value, but can be of different suits.

Flush

All cards must be of the same suit, but don’t have to be in consecutive order.

Straight

All cards must be consecutive, but can be of mixed suits, like this 3, 4, and 5.

Pair + Flush

The cards must contain a pair, and all be of the same suit.

Where did 21 + 3 blackjack come from?

21+3 was first offered as a side bet on a 6-deck shoe at the Las Vegas Hilton in 2001. 

21+3 wasn’t the first side bet using the player’s first two cards and the dealer’s up card (Randy Zinkil’s ‘Lucky Lucky’ was the first I ever saw), but ‘21 3 blackjack’ became the more popular side bet, mostly because it offered casino management several pay tables that allowed them to increase their HA.

This is the original pay table from the Hilton, showing the winning hands and how much you got paid if you had a winning combination.

As you can see, all the winning hands paid the same amount.

The House Advantage (HA) based on this pay table for this side bet on a 6-deck shoe is 3.24%.

Which doesn’t seem like much to give up, when you consider that a double zero roulette game has a HA of 5.26%.

But when a standard 6-deck shoe has a HA of approximately 1.4% against the average player and can be as low as 0.5% or so against a good Basic Strategy player, it means that the HA on the side bet is five or six times greater than the usual HA for a blackjack game.

Which is not good for the players.

And by the way, if you are an average player and want to become a good Basic Strategy player (and who wouldn’t when you can reduce the HA against you by approximately 60%), please check out our other guides on playing Blackjack.

We have several that will take you from beginner to expert (including a very in-depth article on how to be a successful card counter).

You will also find many guides on the other popular casino table games including Roulette, Baccarat, and Craps.

When you look a little deeper into the 21+3 side bet, the less decks in play, the worse the House Advantage for the player. 

In Blackjack, usually fewer decks is better for the players.  

As you can see in the House Advantage table below, with the original Hilton’s 21+3 blackjack side bet, fewer decks can get out of hand very quickly.

The original Hilton game’s rules would give the following HA depending on the number of decks in play.

The House Advantage of the Blackjack 21+3 side bet

On a Double Deck game, the HA on this pay table jumps to 7.26%, which is very strong for the casino.

And on a single deck, it jumps to an outrageous 13.3%.

Why does the House Advantage get so big on this side bet when less decks are in use?

Because there are fewer cards available to make the winning poker hands when there are fewer decks in play.

In the twenty years or so that have passed since the bet was first introduced, there have been many pay tables added.  

Each casino would offer a pay table that would give them the HA that they wanted, while offering odds that they hoped would be more attractive to the player. 

Sometimes they were presented as higher payouts or made available on different versions of blackjack (Double Deck vs. 6-deck shoe etc), but make no mistake, any time a casino adds a side bet to a game, it is to increase their revenue. 

The side bets also increased the volatility of the game, particularly once they added a progressive jackpot as the top award.

This one can be found on some online games.  If it’s on a 6-deck shoe, the HA is 4.14%.

What do these various pay tables tell you?

If you always thought that all the games are the same, these pay tables let you know that each casino makes its own decisions as to how they present their games to their players. So . . . It pays to shop around.

Comparing 21+3 Blackjack with Traditional Blackjack

There really is no comparison between 21 + 3 and a traditional blackjack game.  The side bet is a 3-card-poker bet in addition to the blackjack game and does not impact how the blackjack game plays out at all.

What 21+3 does is offer a more exciting game – not only do you have your blackjack hand in play, but you have a poker hand too.

Strategies for 21+3 Blackjack

In a standard 52-card deck, there are 13 of each of the four suits.  

An example of a suit imbalance is when there are 30 cards left, and 13 of them are clubs, 10 of them are hearts, 3 are spades and 4 are diamonds.

Any suit imbalance is a plus for the player.  

Why is that a plus for the player, you ask?

Let’s say we are playing a Double Deck game, and many of the diamonds and spades are gone, which means that the opportunity to make a flush with clubs or hearts is higher.  If there are 60 cards left and 30 are clubs vs. 10 of the other three suits, there is a greater chance of having 3 clubs dealt together than if there 15 of each suit in the deck. 

And the 21 + 3 bet doesn’t discriminate – a flush is a flush and gets paid the same, no matter the suit.

Techniques for Tracking the Number of Cards in Each Suit

Is it possible to count down the 21+3 side bet? The short answer is YES.

Counting this side bet is challenging for an individual, because you need to keep four separate counts going on simultaneously.

The way to make it work is to have four team members, each one responsible for tracking how many cards of each suit remain in the deck. 

Understanding True Count and Deciding When to Place the 21+3 Wager

Let’s say you’re playing on a 4-deck shoe (for easy math!).  Once the counters have identified that the clubs outnumber the other suits (in the above case by 30 to 10), if you get to a true count of +8 or higher, then the player should make a bet on the Blackjack 21+3 side bet.

With four decks in the shoe, there are 208 cards, 52 of each suit.  With 30 clubs remaining in the shoe, that means there are 22 gone.  You are now +8 in clubs.  

The problem is that it’s a lot of work, it takes four people to do it, and the rewards are minimal at best.  

For example, on a 6-deck shoe game, with a $25 max bet on the 21+3 bet, the counters will win a little over $2 per shoe.

It’s just not worth wasting your time, is it?    

One strategy that is worth your time is when a jackpot reaches a large enough pay out that it means there is a positive expectation for the players. The $34,400 progressive jackpot at the Rampart Casino in Las Vegas (in February of 2024) is probably worth sitting down to play.

Where can you play 21+3?

21+3 is a popular side bet that can be found in many land-based casinos worldwide and also on many live dealer online casino websites.

In the US, it can be found at many of the MGM and Caesar’s Entertainment properties, as well as online.

Expert Advice: Tips for Playing 21+3 Blackjack the Right Way

First up, check the pay table and make sure you’re getting value for money.  The various pay tables entered here are commonly available and they offer widely different House Advantages, so make sure you’re getting the best payout for your bet.

Often you will find that the 6-deck and 8-deck shoes will offer the player the lowest HA, which means over time you may win more or lose less.

Take a look at the progressive jackpot top award pay tables, too.  Often, the casino staff will be able to let you know the usual amount that the progressive hits.  

‘Oh, it usually hits about $20,000 or so.’

If it’s at $30,000, then it may be time to sit down at that table.

Be aware that every side bet on any table game comes with a house advantage in the casino’s favor.  

Usually they are in the low single digits, such as 2%, 3% and so on. But sometimes they come with a huge HA – sometimes as much as 10% or more.

Final Thoughts

So there you have it – how to play the 21 + 3 side bet. It is a fun bet, can be exciting if you find the right pay table, and doesn’t cut into your bankroll by much.

Good luck, and as always, have fun!