# How to Check 21+3: Cards, Payouts and Cost

> Learn which three cards count in 21+3, compare Classic and Xtreme paytables, and check payouts and expected loss using a six-deck model.

- Source: https://toolsgambling.com/blog/21-plus-3-blackjack-side-bet
- Publisher: ToolsGambling
- Published: 2026-10-15
- Updated: 2026-10-15
- Cite as: "21+3 Blackjack Side Bet: Paytables and Expected Cost", ToolsGambling, https://toolsgambling.com/blog/21-plus-3-blackjack-side-bet

**21+3 is a blackjack side bet using the player’s first two cards and the dealer’s upcard to form a three-card poker hand.** It does not depend on those cards adding up to 21. The payout depends on the table’s actual paytable—not just the name Classic or Xtreme.

Under the [Galaxy Blackjack rules published by the Washington State Gambling Commission](https://wsgc.wa.gov/sites/default/files/2023-11/Galaxy%20Blackjack%20amended%206-30-21.pdf), the side bet is placed before any cards are dealt and settled separately from the main wager. A winning blackjack hand is therefore not required for a 21+3 payout, and a winning side bet does not mean the main hand wins. This guide covers those published rules and a separately identified Wizard of Odds paytable, not every version of 21+3.

## Which three cards count?

Only the player’s first two cards and the dealer’s upcard count. The dealer’s hole card and any cards drawn later are excluded; see [page 2 and Appendices G–H on pages 18–19 of the rules](https://wsgc.wa.gov/sites/default/files/2023-11/Galaxy%20Blackjack%20amended%206-30-21.pdf).

For example, a player’s 8♥ and 9♥ combine with the dealer’s 10♥ to make a straight flush: three consecutive ranks of the same suit.

![21+3 instructional diagram showing the player’s 8♥ and 9♥ with the dealer’s 10♥ upcard forming a straight flush](https://toolsgambling.com/media/article/2026/10/09c41881792c8430d7dee9b318314efc.webp)
*Original instructional diagram, not an actual table screenshot; the payout depends on the actual paytable.*

## Which hands qualify?

The paytables covered here pay for four categories: a flush, straight, three of a kind and straight flush. Their payouts appear in [Appendices G and H of the Galaxy Blackjack rules](https://wsgc.wa.gov/sites/default/files/2023-11/Galaxy%20Blackjack%20amended%206-30-21.pdf).

| Hand | Meaning | Example |
|---|---|---|
| Flush | Three cards of the same suit, excluding a straight flush | 2♥, 6♥, J♥ |
| Straight | Three consecutive ranks, not all of the same suit | 8♥, 9♣, 10♦ |
| Three of a kind | Three cards of the same rank | 7♥, 7♣, 7♦ |
| Straight flush | Three consecutive ranks of the same suit | 8♥, 9♥, 10♥ |

These categories are counted separately: a straight flush does not also receive the straight and flush payouts. The same non-overlapping classification is used in the calculations below.

In a multi-deck game, three cards can share both rank and suit—for example, three copies of 7♥ from different decks. The cited PDF paytables do not provide a separate prize for this “suited three of a kind,” so an extra payout must not be assumed.

## How do Classic and the two Xtreme paytables differ?

**The PDF’s Classic paytable pays 9:1 for all four qualifying hands. The two Xtreme paytables differ on straight flush and three-of-a-kind payouts.** Compare every payout rather than relying on the version name.

All ratios below express **net profit** on a winning side bet. The original stake is returned separately.

| Hand | Classic: regulator PDF, Appendix G | Xtreme: regulator PDF, Appendix H | Xtreme: Wizard of Odds |
|---|---:|---:|---:|
| Straight flush | 9:1 | 40:1 | 30:1 |
| Three of a kind | 9:1 | 30:1 | 20:1 |
| Straight | 9:1 | 10:1 | 10:1 |
| Flush | 9:1 | 5:1 | 5:1 |
| No qualifying hand | Stake lost | Stake lost | Stake lost |

The regulator source is **Galaxy Blackjack v5.00, May 31, 2017, amended June 30, 2021**, [Appendices G–H, pages 18–19](https://wsgc.wa.gov/sites/default/files/2023-11/Galaxy%20Blackjack%20amended%206-30-21.pdf). It permits these versions with 2–8 decks; it does not establish the rules of every casino table. The [Wizard of Odds analysis](https://wizardofodds.com/games/blackjack/side-bets/21plus3/), updated August 3, 2026, analyzes a flat 9:1 schedule and an Xtreme schedule of **30/20/10/5**, among other versions. It is not the same paytable as the regulator PDF’s **40/30/10/5**.

This is not an exhaustive list. [Galaxy Gaming’s product page](https://www.galaxygaming.com/products/21-3), checked October 15, 2026, describes Xtreme as customizable and describes winning hands as a straight or better. That product description does not establish a particular operator’s payouts. Neither Xtreme schedule above should be treated as universal.

### What does 9:1 pay on a \$5 bet?

A winning \$5 bet at 9:1 earns **\$45 in net profit**, for a **\$50 total return including the original stake**.

- Net profit: `$5 × 9 = $45`
- Total return: `$45 + $5 = $50`

For comparison, a straight flush under the regulator PDF’s Xtreme schedule pays 40:1: a \$5 stake earns **\$200 in net profit** and a **\$205 total return**. These examples assume a qualifying hand under the [specified PDF paytable](https://wsgc.wa.gov/sites/default/files/2023-11/Galaxy%20Blackjack%20amended%206-30-21.pdf). They describe individual winning outcomes, not the expected result of repeated bets.

## What does 21+3 cost in a six-deck model?

The modeled house edge is **3.24% for Classic 9/9/9/9, 6.07% for the regulator PDF’s Xtreme 40/30/10/5, and 13.39% for Wizard of Odds’ Xtreme 30/20/10/5**. The 13.39% figure must not be attributed to the PDF version.

House edge measures expected loss per unit of side-bet stake. It is neither the probability of losing nor a percentage of the main blackjack wager.

### What probabilities does the model use?

The model counts all unordered three-card combinations from a fresh six-deck shoe of 312 cards, with no information about other exposed or previously dealt cards.

`C(312, 3) = 312 × 311 × 310 / 6 = 5,013,320`

The category counts match the six-deck counts in the [Wizard of Odds mathematical analysis](https://wizardofodds.com/games/blackjack/side-bets/21plus3/).

| Non-overlapping category | Three-card combinations |
|---|---:|
| Straight flush | 10,368 |
| Three of a kind | 26,312 |
| Straight | 155,520 |
| Flush | 292,896 |
| Loss | 4,528,224 |
| **Total** | **5,013,320** |

To reproduce the house edge, let `a`, `b`, `c` and `d` be the net-profit payout multipliers for straight flush, three of a kind, straight and flush:

`House edge = [4,528,224 − (10,368 × a + 26,312 × b + 155,520 × c + 292,896 × d)] / 5,013,320`

| Paytable | Multipliers: `a / b / c / d` | House edge before rounding | Rounded |
|---|---|---:|---:|
| Classic from the PDF | 9 / 9 / 9 / 9 | 3.238572% | **3.24%** |
| Xtreme from the PDF | 40 / 30 / 10 / 5 | 6.073101% | **6.07%** |
| Xtreme from Wizard of Odds | 30 / 20 / 10 / 5 | 13.389610% | **13.39%** |

The PDF Xtreme percentage is **our calculation using the formula above and Wizard of Odds’ modeled category counts**, not a percentage declared by the regulator.

The probability of any payout is the same across these three models because they use the same winning categories:

`(10,368 + 26,312 + 155,520 + 292,896) / 5,013,320 × 100% = 9.676143%`

That is **not theoretical RTP**. Theoretical RTP equals one minus the house edge and accounts for payout amounts, not just how often a qualifying hand occurs.

### How does house edge translate into expected loss?

Expected loss equals total side-bet turnover multiplied by the applicable house edge.

For a hypothetical **100 bets of \$5** under the six-deck Classic model:

`Turnover = 100 × $5 = $500`

Using the unrounded modeled house edge gives an expected loss of approximately **\$16.19**. Using the rounded **3.24%** gives:

`$500 × 0.0324 = $16.20`

The difference comes from rounding the percentage. This assumes the stated six-deck paytable and model throughout; it is an expectation, not a forecast of personal losses. Actual results over 100 rounds can differ substantially.

## How can you check a table and model its cost?

First confirm the table’s deck count and every paytable row; only then use a matching house edge. A shared version name is not enough.

Use this repeatable check:

1. **Find the deck count in the table rules.** The percentages above apply to six decks only.
2. **Open that table’s paytable.** Compare straight flush, three of a kind, straight and flush separately.
3. **Check for extra categories or exceptions.** A separate suited-three-of-a-kind prize or another rule change means the percentages above cannot automatically be reused.
4. **Check what the payout notation means.** In the cited schedules, 9:1 means nine stakes of net profit plus return of the original stake—not a total return of nine stakes.

The [ToolsGambling House Edge Calculator](https://toolsgambling.com/casino/house-edge-calculator) models expected loss **from an already known house edge**. It does not identify table rules, select a 21+3 paytable or calculate the distribution of three-card hands.

To reproduce the rounded Classic cost example:

- Check **Enter a custom house edge**.
- Enter a house edge of **3.24%**.
- Enter **\$5** in **Bet Size per Round**.
- Select **By rounds**.
- Enter **100** in **Number of Rounds**.

The result is approximately **\$16.20**, because the entered percentage is rounded. Do not use **Blackjack (basic strategy)** as a 21+3 calculation: that preset concerns the main game.

If the deck count or paytable differs, a matching mathematical calculation is needed first; substituting the nearest familiar percentage is not valid. Decisions on the main hand are covered separately in the [blackjack guide](https://toolsgambling.com/blog/blackjack-tips) and should not be confused with modeling the side bet’s cost.

## FAQ

### Does a pair pay in 21+3?

A pair alone does not pay under Classic or Xtreme in Appendices G and H of the Galaxy Blackjack rules. However, the three cards may qualify for another category: in a multi-deck game, two cards of the same rank do not rule out a flush. Check all three cards against the table’s paytable.

### Does blackjack basic strategy help with 21+3?

Basic strategy governs decisions on the main blackjack hand, not the 21+3 side bet. The side-bet hand is fixed by the player’s first two cards and the dealer’s upcard; later decisions on the main hand do not change it.