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21+3 Blackjack Side Bet: Complete Guide | LeoVegas

21 + 3 Blackjack Side Bet: A Comprehensive Guide

Blackjack has remained a casino staple thanks to its straightforward rules and mix of chance and decision-making. While the goal of beating the dealer without going over 21 remains unchanged, many tables now include optional side bets that add extra variety and entertainment to each round.

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One of the most popular side bets is the 21 + 3 side bet, which forms a three-card poker-style hand using the player's two cards and the dealer's upcard. Wins are based on poker-style combinations like flushes, straights, or three of a kind, and are independent of the main blackjack game outcome. Simple to understand and quick to resolve, 21 + 3 adds a poker-inspired twist to traditional blackjack play.

Understanding the 21 + 3 Side Bet

The 21 + 3 side bet was introduced in the early 2000s when Texas Hold’em was seriously trending, as a way to add a little poker-style twist to standard blackjack play. It uses familiar three-card poker hand rankings to evaluate a combination made from the player’s two cards and the dealer’s upcard. Over time, different versions of the bet have emerged, each with slight variations in hand payouts and available combinations.

This bet is placed before any cards are dealt. After receiving two cards and seeing the dealer’s upcard, those three cards are assessed as a poker hand. If they form a qualifying combination, the side bet pays out based on the specific table’s payout chart. Regardless of the side bet outcome, the regular blackjack hand continues as normal.

Rules and Payout Structure

Placing a 21 + 3 side bet is straightforward. At the beginning of the round, before the cards are dealt, you will have the option to make this additional wager. Most tables will have a designated betting circle or area labelled “21 + 3”. Once the cards are dealt, you will receive two cards. The dealer will reveal their upcard, and these cards are evaluated to see if they form a winning poker hand. The winnings are based on the payout table in use.

Payout and Payout Tables Variations

There are several versions of 21 + 3 payouts, varying slightly depending on the casino, software provider, and table variant. The most common winning combinations typically include:

  • Suited Trips: Three cards of the same rank and suit
  • Straight Flush: Three consecutive cards of the same suit
  • Three of a Kind: Same rank, different suits
  • Straight: Three consecutive cards, mixed suits
  • Flush: Three cards of the same suit, non-consecutive

When it comes to payout tables, the standard payout table for 21 + 3 often looks like this:

HandStandard Payout
Suited Trips100 to 1
Straight Flush40 to 1
Three of a Kind30 to 1
Straight10 to 1
Flush5 to 1

Alternative payout tables also exist and may offer different returns. An example of an alternative payout table is:

HandAlternative Payout
Suited Trips35 to 1
Straight Flush20 to 1
Three of a Kind20 to 1
Straight10 to 1
Flush5 to 1

Some versions simplify things even further by only paying for straights and higher, skipping flushes entirely. It’s worth checking the paytable first, especially if you’re playing at a new casino.

Possible Winning Hands and Their Rankings

As established, the 21 + 3 side bet is based on forming a three-card poker hand using your two cards and the dealer’s upcard. Each hand comes with its own payout and ranking, with higher rewards tied to less frequent combinations. Here’s a breakdown of the possible winning hands:

Suited Trips

The rarest and highest-paying hand in the 21 + 3 side bet.

It consists of three cards of the same rank and the same suit, like three Queens of Hearts. Since all three cards must be identical, the odds of hitting this combination are low, but the rewards are high. As noted in the standard payout table, this hand typically pays 100 to 1.

Straight Flush

A straight flush is three consecutive cards of the same suit. It is a strong hand that is tough to achieve, but more common than suited trips. Note that an ace can be low or high, but not both. For example, K-A-2 will not be considered a straight flush. The typical payout for this hand is 40 to 1.

Three of a Kind

This hand requires three cards of the same rank, regardless of suit. It’s less rare than suited trips and usually pays 30 to 1.

Straight

A straight is made up of three cards in numerical order, like 4-5-6, with no requirement for matching suits. It shows up more often than a straight flush and typically pays 10 to 1.

Flush

A flush consists of any three cards from the same suit, without needing to be in order. It’s the most common winning hand in 21 + 3 and usually pays 5 to 1. Because it hits more often, it adds steady moments of action to the game.

Odds and House Edge

While the 21 + 3 side bet adds variety to the game, it comes with a higher house edge than standard blackjack. The bet is based purely on chance and follows a high-volatility structure.

In a typical 6-deck game using standard payouts, the odds of landing a winning combination are roughly:

HandProbability
Suited Trips0.02%
Straight Flush0.22%
Three of a Kind0.24%
Straight3.26%
Flush4.96%
Any Win8.7%

The house edge varies depending on the payout structure used at the table:

  • Standard Paytable: ~3.24%
  • Alternative Paytable: ~6.29%
  • Favourable Paytable: ~2.74%Lower payouts increase the house edge, reducing the long-term return for players. While 21 + 3 has a higher edge than regular blackjack, it’s still less punishing than some other side bets like Perfect Pairs, Insurance, or Lucky Ladies.

Comparison with Other Blackjack Side Bets

Many blackjack tables include side bets in addition to 21 + 3, each with its own rules and appeal. Some of the most widely used bets include Perfect Pairs, Insurance, and Lucky Ladies. Here’s how 21 + 3 stacks up against them in terms of structure and gameplay.

21 + 3 vs. Perfect Pairs

Perfect Pairs is a side bet that pays when your initial hand forms a matching pair. The payouts typically fall into three categories: a Perfect Pair (two identical cards, both in rank and suit), a Coloured Pair (same rank and same colour, but from different suits), and a Mixed Pair (matching rank with no restriction on suit or colour).

Both Perfect Pairs and 21 + 3 are based entirely on chance and resolved separately from the main blackjack hand. 21 + 3 tends to offer a wider variety of qualifying hands and, depending on the table’s pay structure, often comes with a lower house edge. These structural differences make the two bets distinct in how they play out and how frequently they hit.

21 + 3 vs. Insurance Bet

The Insurance Bet is only available when the dealer’s upcard is an ace and pays 2:1 if they have a natural blackjack. Despite this seemingly protective function, the house edge can exceed 7% in multi-deck games, making it statistically unfavourable for most players over time.

By contrast, 21 + 3 is not tied to a specific dealer outcome and can be played on any hand. As mentioned, its structure revolves around multiple potential combinations, each with its own odds and payouts, which gives it a different risk profile and a more varied style of play.

21 + 3 vs. Lucky Ladies & Royal Match

The Lucky Ladies side bet pays when your first two cards total 20, with higher payouts for matched or suited cards. Some versions pay up to 1,000:1 for specific combinations, but the house edge is often above 24%.

Royal Match pays if your first two cards are suited, with premium payouts for a suited King and Queen. Depending on the table, payouts can reach up to 75:1. The house edge varies but typically ranges from 3% to over 10%.

Compared to both, 21 + 3 has more frequent qualifying outcomes and a lower house edge, generally between 2.74% and 6.29%, depending on the paytable.

Should You Play the 21+3 Side Bet?

21 + 3 is one of the most entertaining and widely played blackjack side bets, but whether it is right for you depends on your goals at the table. The pros and cons of the bet are as follows:

Pros

  • Covers multiple hand types, giving more chances to win compared to single-outcome side bets like Insurance or Perfect Pairs
  • Simple to follow and resolves quickly each round
  • Adds variety without needing additional decision-making
  • Generally has a lower house edge than other side bets like Insurance, Lucky Ladies, or Perfect Pairs

Cons

  • Higher house edge than standard blackjack, ranging from 2.74% to over 6%
  • Winning hands appear in fewer than 1 in 10 rounds
  • Entirely chance-based, with no room for strategic input

Like most side bets, 21 + 3 adds a bit of risk and extra cost to each hand. It brings more action to the table, but it isn’t designed for consistent returns. If you’re okay with that trade-off, it can be a fun way to mix things up now and then.

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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