What is 21+3 Blackjack Side Bet and how to place it? | LeoVegas

21+3 Blackjack Side Bet


The 21+3 Blackjack Side Bet is a popular addition to online blackjack, involving a separate wager on the combination of your two initial cards and the dealer's face-up card. The side bet offers various payouts based on poker hand combinations, such as Pair Flush, Flush, Straight, Three of a Kind, Straight Flush, and Three of a Kind Flush.

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Blackjack has evolved over the years. You’ll still find the classic game of 21 wherever you go in land-based casinos, but online, there are many variants ready for you to test your blackjack skills which include side bets. One of the most popular is 21+3 blackjack.


So, what is 21+3 in blackjack? Well, it’s a side bet that you can take in 21+3 blackjack games that draw from your dealt cards and the dealer's face-up card. If you call the side bet correctly in a 21+3 blackjack game, you can win more money at rather good odds.

Here, you’ll find out what 21+3 is in blackjack as well as how to play this popular blackjack side bet, the odds, payout, house edge, and some replies to frequently asked questions on the topic.


What Is the 21+3 Side Bet?

The 21+3 side bet is an additional betting option found in games of 21+3 online blackjack. The side bet you’re backing is that the two original cards dealt to you combined with the dealer’s up card will create a winning combination. The winning combinations, of which there are four or five, draw from three-card poker.

So, the 21+3 side bet is a way to place your chips on another possible outcome in blackjack. As it gets resolved independently of your initial blackjack bet and doesn’t impact the rest of the round, it’s a fun little way to make even the opening exchanges more exciting.

As is the case in casino poker, your 21+3 side bet in blackjack has a range of payouts. These payouts follow the poker hand tier system to determine winners, but rather than play as a hand hierarchy. The tougher hands tend to pay more. So, the side bet’s return can vary greatly from win to win.

How to Play Blackjack 21+3 Side Bet

To play the 21+3 blackjack side bet, you’ll need to be sure to place a wager in the 21+3 side bet position before you commence the game. Depending on the game, the layout of your betting zones on the felt will differ. Generally speaking. However, you’ll have betting zones that circle the main game bet circle, one of which will say 21+3 inside of its borders.

To be in with a chance of winning a 21+3 blackjack side bet, you’ll need to place chips in this 21+3 betting zone before the round begins, as well as the playing zone – as you’d expect. Once your chips are down, and you're ready to test your luck, press play to get your cards.

Most games of 21+3 blackjack allow you to double down on values of nine or above, split for the first two cards of potential blackjack hands, and win with blackjack, which usually pays 3:2. With a 21+3 side bet, you could also win as soon as the cards are drawn.

With a 21+3 blackjack side bet down, you’ll be hoping that the two cards in your hand and the dealer’s up card combine for a three-card poker hand. If you have a successful 21+3 side bet, you’ll be paid immediately, and your regular bet will stay in, allowing you to play through the whole round.

To win a 21+3 blackjack side bet, you will require one of these three-card combinations:

  • Pair Flush: Find a value pair that are of the same suit (6 of Diamonds, 6 of Diamonds)
  • Flush: Get three cards of the same suit (Ace of Hearts, 3 of Hearts, 9 of Hearts)
  • Straight: Combine three cards of consecutive values (5, 6, 7 of any suit)
  • Three of a Kind: Have three cards of the same value showing (2 of Hearts, 2 of Clubs, 2 of Spades)
  • Straight Flush: Show three cards of consecutive values and of the same suit (4 of Clubs, 5 of Clubs, 6 of Clubs)
  • Three of a Kind Flush: Get three cards of the same value and of the same suit (7 of Clubs, 7 of Clubs, 7 of Clubs)Most 21+3 blackjack tables are played with a shoe of six or more decks. So, while still very much a long shot, some tables do payout for the Three of a Kind Flush when the dealer’s up card and player’s hand all show the same card.Each of the winning hands listed above pays a very different odds and value if you back the 21+3 side bet. In most cases, the Pair Flush offers the shortest odds for a return, while the Three of a King Flush tops the board. Importantly, the returns will vary from table to table. Some pay flat odds on any 21+3 blackjack win, while others mix it up.


21+3 Blackjack Side Bet Odds

To discuss the 21+3 blackjack side bet odds, we will delve into the probability and likelihood of each of the cards and the dealer's winning hands appearing in the game. For the odds that reflect the returns in a game of 21+3 blackjack, go down one more bump.

On the assumption that six decks are in play for your game of 21+3 blackjack – and that it pays for a Pair Flush, Flush, Straight, Three of a Kind, Straight Flush, and Three of a Kind Flush – these are the probabilities that you’ll win on each hand when you place a 21+3 blackjack side bet:

  • Pair Flush: 0.01120
  • Flush: 0.05842
  • Straight: 0.03102
  • Three of a Kind: 0.00504
  • Straight Flush: 0.00207
  • Three of a Kind Flush: 0.00021 In theory, you can win the three-card side bet and get 21 from your hand, lending the name 21+3 blackjack and answering the question of what is 21+3 in blackjack, because you get two chances to make winning hands.

As you can see, the probability of a 21+3 side bet coming in for any kind suited hand is much lower than not – which has a probability of around 0.9.

21+3 Blackjack Side Bet Payout

The 21+3 blackjack side bet payout varies from table to table. You can find some tables that simply pay 9:1 for a 21+3 side bet win, regardless of the winning hand itself. In general, this means that you’ll make slightly more on returns for more probable hands, like a Flush, but miss out on much larger pays for the likes of a Straight Flush.

The payout odds also vary on 21+3 blackjack side bets with tables that vary the pay. Overall, you can expect to see payouts similar to these for winning 21+3 blackjack side bet hands:

  • Pair Flush: 2:1
  • Flush: 5:1
  • Straight: 10:1
  • Three of a Kind: 30:1
  • Straight Flush: 40:1
  • Three of a Kind Flush: 100:1

With so much variety on the returns for 21+3 blackjack side bets, it’s wise to try out different games. You may find that you have a knack for hitting the low three-card combos, for example, so the flat-rate odds of around 9:1 might be better. Then again, hitting a Straight Flush to only return 9:1 could be a bit disappointing.

The game you pick depends entirely on how you want casinos to balance risk with the optional side bet and how often you plan to put down a 21+3 blackjack side bet.

21+3 Blackjack House Edge

As with payouts, the 21+3 blackjack house edge varies greatly between each table. The factors influencing this are its paytable (how many three-card combinations it will pay on) and the number of decks in play. The house edge reduces whenever more decks are in play for a game of 21+3 blackjack.

In a game of six decks that pays on Flush, Straight, Three of a Kind, Straight Flush, and a Three of a Kind Flush at varying payouts (not a flat 9:1 rate), the 21+3 blackjack house edge sits at 4.14%. Eight decks six deck shoe would lessen the house edge to 3.18%, while only three decks in the shoe would send it up to 7.76%.

Blackjack 21+3 FAQ

Here are some quick-fire answers to frequently asked questions on what 21+3 is in blackjack.

Is 21+3 part of the standard blackjack game?

21+3 isn’t part of the standard blackjack game and is only available as a side bet in some variants.

How do you know if 21+3 is available at a blackjack table?

You will know if 21+3 is available at a blackjack table casino if you can see a betting zone on the green felt that reads “21+3” or if the game is called “21+3 Blackjack”.

Can you use card counting with a 21+3 blackjack bet?

It’s very unlikely that card counting techniques will be useful in playing 21+3 blackjack simply because of the variations of suits and values that make winning hands, as well as there usually being six or more decks in play.

Is 21+3 a good side bet in blackjack?

21+3 is as good a form of a side bet as any in blackjack. They tend to have longer odds as they’re less likely to happen than even getting blackjack, but they can add to the entertainment factor for some players.

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