21+3 Blackjack: The Side Bet That Brings Poker In!

21+3 blackjack is a popular side bet combining your two cards with the dealer’s upcard to form poker-style hands like flushes, straights, or three of a kind. Winning hands pay out based on rarity, with suited three of a kind offering the highest payout—typically 100 to 1. While it adds excitement, 21+3 has a higher house edge than standard blackjack and should be played for fun rather than strategy.

If you’ve been playing blackjack for a while, chances are you’ve seen that little “21+3” box sitting next to the main betting circle and thought, “What is that about?” Maybe you’ve ignored it, or maybe you’ve tossed a few chips on it just for fun. Either way, it’s time we actually talk about what 21+3 blackjack is, how it works, and whether or not it’s worth your chips. 

I’ve been around blackjack tables long enough to see players either fall in love with this side bet or burn through their stack chasing it. But once you really understand how it works and what you’re betting on, it starts to make a whole lot more sense. 

What Is 21+3 in Blackjack? 

Let’s keep this simple. The 21+3 blackjack side bet is a wager based on your two cards plus the dealer’s upcard. That’s where the “+3” comes from. You’re not betting on your hand against the dealer anymore; you’re playing a little poker on the side. 

So what are you hoping to hit?  

You’re looking for poker-style combinations, using those three cards: 

• Flush (all same suit) 
• Straight (sequential cards, like 5-6-7) 
• Three of a Kind 
• Straight Flush 
• Suited Three of a Kind 

Now, that last one? That’s the holy grail of 21+3: three identical cards of the same suit. I’ve only seen it hit a few times in person, but when it does? That table erupts. 

How Does 21+3 Work at the Table? 

Before any cards are dealt, you place your main blackjack wager and, if you want, a chip or two on the 21+3 side circle. Once cards hit the felt, the dealer checks the combination of your two cards and their face-up card. If those three form a qualifying hand, you win the side bet. 

Let me be clear, though: your blackjack hand still plays out normally. This is just a side action. A little bonus bet, if you will.

21+3 Blackjack Payouts 

Payouts vary a little depending on the casino or the online blackjack platform you’re using, but here’s the common breakdown: 

• Flush – 5 to 1 
• Straight – 10 to 1 
• Three of a Kind – 30 to 1 
• Straight Flush – 40 to 1 
• Suited Three of a Kind – 100 to 1 

Let that last one sink in 100 to 1. Drop a $10 chip on that and you’re walking away with a grand. But yeah, don’t count on it showing up every session. 

Is It Worth Playing? 

Ah, the million-dollar question. Or at least the hundred-dollar question, depending on your betting limit. 

21+3 is a high-risk, high-reward bet. It’s not meant to be your bread and butter like the core game of blackjack is. It’s more like a spice, something you sprinkle into it to add flavor. 

From a purely strategic standpoint, the house edge on 21+3 is higher than the main game. That’s no secret. But I’ve had nights where hitting a few straights or flushes early kept me in the game longer than my actual blackjack hands did. 

If you’re chasing a blackjack bonus or just enjoying a casual session online, adding a little side bet can crank up the fun. Especially when there’s an online blackjack bonus on offer, some platforms will even toss in free side bets or extra perks for 21+3 play. 

Online Blackjack and 21+3 Side Bets 

These days, you don’t even need to hit a physical casino to try out 21+3. Most online blackjack games now offer the option to add the side bet before every hand. If you’re new to the format, I’d suggest starting small; maybe even find an online blackjack no deposit bonus to try it out without risking your own cash. 

Some platforms even offer blackjack sign-up bonuses that include side bet incentives. It’s worth shopping around for a site that gives you a little extra play money just for signing up. 

Want to really maximize value? Look out for an online blackjack bonus that applies to side bets. Not all of them do, but when they do, it’s like finding free money on the table. 

Tips for Playing 21+3 Like a Pro 

Let me drop a few tips I’ve learned over the years: 

• Don’t chase the payouts. The 100-to-1 hit is awesome but rare. Don’t bet big hoping to hit it. Play within your bankroll. 
• Stick to games with good payout structures. Some tables offer worse odds. Always check the 21+3 blackjack payouts before committing. 
• Pair it with a solid blackjack game. Look for tables that pay 3:2 on blackjack, not 6:5. If you’re giving the house an edge on the side bet, at least don’t let it rob you on the main game too. 
• Mix it up. Use it to keep sessions interesting, but don’t make it your only play. Side bets should complement your game, not dominate it. 

10 Unforgettable 21+3 Moments 

Flush Win 

I had the King and Ten of hearts, and the dealer showed a Six of hearts—flush! My side bet paid immediately. (Main hand? No luck, but I didn’t mind.) 

Straight Flush Burst 

Holding Ace and 2 of diamonds, I saw the dealer flip a 3 of diamonds. Straight flush! A mini jackpot in the middle of regular blackjack play. 

Low Pair Outcome 

My two 5s plus the dealer’s 5 gave me three of a kind, a great payout. I increased my 21+3 bet in the next round—no luck, but it was worth the excitement. 

No Win Round 

My 7 and 5 of clubs against the dealer’s 2 of hearts—no match. It reminded me that side bets run hot and cold, so I eased off for a while. 

Student’s Random Flush 

A student tried a side bet on a whim and landed a flush with the 9 and Queen of spades, plus the dealer’s 5 of spades. That win made them more confident in experimenting with 21+3. 

Surprising Pair 

I was dealt two Kings of clubs, and the dealer revealed a King of diamonds—three of a kind! That win carried me through the session. 

Missed Straight Flush 

My 4 and 6 of hearts looked promising, but the dealer flipped a 5 of clubs. I hit a straight but not a flush. Still a solid win, but I couldn’t help wishing for that 5 of hearts. 

Demo Session High 

During a practice game I ran, we saw a 10, Jack, and Queen of spades—a perfect straight flush. It was a great moment to showcase the thrill of 21+3. 

Near Miss Straight 

I had the Jack and Queen of clubs, and the dealer showed a King of hearts. It completed a straight, but I couldn’t help wondering about the payout if that King had been clubs. 

Late-Night Jackpot 

My personal favorite: I held the 6 and 7 of spades, and the dealer’s upcard was an 8 of spades. Straight flush under the neon lights—I took that as my cue to call it a night on a high note. 

FAQs

1. Which hands pay out in 21+3?

Typical qualifying hands include Three of a Kind, Straight, Flush, and Straight Flush. Specific payouts vary by casino and table rules, so always confirm paytables before playing.

2. Is the house edge higher on 21+3 than in regular blackjack?

Yes. Side bets generally carry a higher house edge than standard blackjack, meaning the casino’s advantage is bigger. It’s a fun addition, but less favorable from a purely mathematical standpoint.

3. Can I apply a strategy to win the 21+3 bet more often?

Because the outcome depends heavily on luck (and the dealer’s up-card), no reliable counting method or advanced strategy can consistently lower the house edge. Most players treat it as a fun, higher-risk bet.

4. Does the outcome of the 21+3 side bet affect the main blackjack hand?

No. The side bet is resolved independently. You can win or lose the 21+3 wager regardless of what happens in the main blackjack round.