21 + 3 Blackjack – Free Game, Rules, Strategy & Odds

Adding a 3-Card Side Bet to Blackjack Gives a Whole New Experience

Many casinos have tried to make blackjack more interesting (and often increase their house edge) by using side bets. Popular examples include 777 or Perfect Pairs. 21 +3 Blackjack is a regular game which can be either European or US rules, which has a 3-card optional side bet. The idea is that you make a poker style hand with your first 2 cards in combination with the dealer’s up card. There are some big payouts possible. These depend on the pay table in use – there are several variations. 21 +3 Blackjack can be played online and in live casinos.

This page gives you a complete overview of 21+3 Blackjack. I have used the live version as a basis, using the US rules – though the format is the same with European blackjack rules. First you will find an overview of the game, followed by some notes on strategy. Pros and Cons of this side bet are covered after that.

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  • Overview of 21+3 Blackjack

    The 21+3 side bet is optional, and its size does not need to be the same as the main bet. In order to play the side-bet, you need to participate in the main hand.

    Placing a bet in the 21+3 square is all you need to do to participate. As soon as the deal is made, and before any player takes any actions the 2 player cards and the dealer’s up-card (or only card in European Blackjack) are compared to the pay table.

    There are several variations of 21+3 payouts, the most simple pays from a ‘flush +pair’ and up, with 9-to-1 payouts in each case. When pairs are also included, this is hit more often, so the prizes are lowered to reflect this. There are 3-to-1 for all hands (pair, flush, straight, trips and straight flush) or there are staggered pay tables.

    When the prizes are staggered, a straight flush or better can win significant money. Here is an example:

    • Flush – Pays 5:1
    • Straight – Pays 10:1
    • Straight Flush – Pays 35:1
    • Three of a Kind – Pays 33:1
    • Suited 3 of a Kind – 100:1

    Keep in mind that depending on the pay table, the house edge can get as high as 13% for this side bet. You can find examples of games (depending on the number of decks in use) where this is around 2.78% instead.


    Strategy for 21+3 Blackjack

    It goes without saying that knowing the correct basic strategy of the base game is a prerequisite here. Without this you are just handing money to the house.

    Your main ‘strategy’ decision over the long run with the 21+3 side-bet is whether to play or not. The house edge is bigger than in most base games. If you know this, then you get to decide whether the added interest and entertainment (and chance of a windfall win) are worth it to you. If the extra engagement from the 21+3 bet works for you – then you can simply add a little to your bankroll to cover this.

    Card counters can beat this game by memorizing the suits as they are dealt. It is possible on some deals to find one suit over-represented as the shoe gets smaller – turning the edge positive for players. The expected hourly rate for this is very low compared to other forms of counting. Online the deck is shuffled after each hand, making card counting impossible.


    Pros and Cons of 21+3 Blackjack

    Adding a poker style hand to blackjack makes for an interesting variation – though I do wonder whether ‘purists’ in either discipline would approve! Depending on which of the pay tables you use there is the chance of a 9-to-1 or even bigger windfall. That elusive suited 3-of-a-kind (paying 100-to-1) would certainly be memorable.

    Whether you participate depends on your attitude towards side-bets in general. Some players like these bets, and are happy to pay the extra house-edge for the chance of the occasional big win. Others scorn these bets as long-term losers.

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    Summing Up – How Does 21+3 Blackjack Compare?

    This is an interesting side bet, though there are plenty more to choose from. The jackpot potential of the 777 side bet appeals to many players, and the regular payouts for Perfect Pairs is also popular. For me the 21+3 bet compares well, and is sure to have its fans.

    Casino software house WagerWorks have produced an online version of this game – along with the Unibet Casino.