21+3: a poker bet on your first three cards
21+3 is a blackjack side bet that turns your first two cards and the dealer’s upcard into a three-card poker hand. A flush, straight, three of a kind or straight flush wins. It has no effect on your blackjack hand.
Reviewed Oct 15, 2026
Answer first
90s- 01The bet is settled right after the first cards are dealt.
- 02Common paytables pay up to 100 to 1 for suited three of a kind.
- 03The house edge is usually about 3% to 5%, higher than good blackjack.
Key numbers
21+3 in four numbers
In short
Key takeaways
- 21+3 is separate from your main bet.
- Win or lose, your blackjack hand plays as normal.
- Paytables differ; read the felt.
- A flush is the most common winner.
On the felt
A winning 21+3
Your cards
Seven and eight of hearts
Dealer upcard
Nine of hearts
Result
Straight flush: 40 to 1
Your blackjack hand of 15 still plays on.
Pay table
Common 21+3 paytable (6 decks)
Glance before you bet
| Hand | Pays |
|---|---|
| Suited three of a kind | 100 to 1 |
| Straight flush | 40 to 1 |
| Three of a kind | 30 to 1 |
| Straight | 10 to 1 |
| Flush | 5 to 1 |
Other tables pay 9 to 1 on any winner.
How the bet works
You place the 21+3 bet beside your main bet before the deal. When the dealer shows the upcard, your two cards and that card form a three-card hand. Paying hands are settled at once.
Your main blackjack hand then continues as normal. Hitting, doubling or splitting does not change the 21+3 result.
Rough chance of each hand (6 decks)
| Hand | About 1 in |
|---|---|
| Suited trips | 4,800 |
| Straight flush | 490 |
| Three of a kind | 200 |
| Straight | 33 |
| Flush | 17 |
Approximate; varies with decks.
Why the edge is higher
A good blackjack game with basic strategy has an edge near 0.5%. Most 21+3 paytables carry an edge of 3% to 5%, so the side bet costs more per dollar than the main game.
The fast settlement and big pays make it fun, but treat it as a small extra.
Sequence
Playing 21+3 sensibly
Step 01
Read the paytable
Pays differ.
Step 02
Keep it small
A fraction of your main bet.
Step 03
Ignore past results
Every deal is new.
Step 04
Never change basic strategy
The side bet is settled.
Step 05
Skip it on a tight budget
Edge is higher.
Versions you will see
The original version paid 9 to 1 on any flush, straight or three of a kind. Many casinos now use tiered tables like the one above. Some add a bonus for suited trips matching the dealer.
Online and live dealer blackjack often include 21+3 alongside Perfect Pairs.
Floor rules
21+3 terms
Know before you sit
- Upcard
- The dealer’s face-up card.
- Flush
- Three cards of one suit.
- Straight
- Three ranks in a row.
- Suited trips
- Three identical cards.
Comparing it to Perfect Pairs
Perfect Pairs pays on a pair in your first two cards, while 21+3 needs a three-card poker hand. 21+3 wins more often but pays less on most hands.
Both are settled at once and both have higher edges than the main game.
Cost per 100 hands at $5 (rough)
| Bet | Expected loss |
|---|---|
| 21+3 at about 3.5% | About $18 |
| Perfect Pairs at about 6% | About $30 |
| Main bet at 0.5% | About $2.50 |
Rough figures.
Common mistakes
- Betting more than the main bet
- Keep it small.
- Changing play for the side bet
- It is already settled.
- Assuming one paytable
- Read the felt.
- Chasing a suited trips
- It is rare.
Keep reading
Related pages
Go play
Where to play in Las Vegas
Tap a resort — each row opens that casino’s White Gambling page (hours, game mix, floor facts). Venues with this game in official counts, sorted high to low.
Open a casino page
Real listings · not adsAfter the 90 seconds
Questions before and after you play
A 90-second guide cannot cover every table moment. Tap a group, then a question — answers are short paragraphs, not one-liners.
01Basics
What is 21+3?
A side bet that your two cards plus the dealer upcard make a flush, straight, trips or straight flush.
Does it affect my hand?
No. Your blackjack hand plays as normal. House rules can vary, so check the table placard or ask the dealer.
When is it paid?
Right after the first cards are dealt. House rules can vary, so check the table placard or ask the dealer.
02Payouts
What does it pay?
Common tables pay 5 to 1 for a flush up to 100 to 1 for suited trips. House rules can vary, so check the table placard or ask the dealer.
What is the most common win?
A flush, which lands about once every 17 hands with six decks. House rules can vary, so check the table placard or ask the dealer.
Is 9 to 1 for everything better?
It depends on decks; check the edge for your game. House rules can vary, so check the table placard or ask the dealer.
03Value
What is the house edge?
Usually about 3% to 5%, depending on the paytable and the number of decks. House rules can vary, so check the table placard or ask the dealer.
Can card counting help?
Only slightly in theory; it is not practical. House rules can vary, so check the table placard or ask the dealer.
Is it online?
Yes, often in live dealer blackjack. House rules can vary, so check the table placard or ask the dealer.
Sources
- Wizard of Odds — 21+3 Not from a registry (Reference source, not an official registry)The gaming industry’s standard reference for casino-game math, by actuary Michael Shackleford. Not an official registry; our calculators compute these numbers independently. · accessed Oct 15, 2026Rules, odds and house edge
- Nevada Gaming Control Board · accessed Oct 15, 2026Approved games and gaming revenue reports
- UNLV Center for Gaming Research Not from a registry (Reference source, not an official registry) · accessed Oct 15, 2026Research library on casino games and gambling
- National Council on Problem Gambling — Help and resources Not from a registry (Reference source, not an official registry) · accessed Oct 15, 2026Free, confidential help: call or text 1-800-GAMBLER