A straight flush combines two conditions in the same hand: the card ranks are consecutive, and every card has the same suit. In standard five-card poker, 5♣–6♣–7♣–8♣–9♣ is a straight flush.
The term is not always limited to five cards. Three-card and four-card casino games can define shorter straight flushes, so the game rules and paytable determine the required hand length.
Both tests must be satisfied
| Hand | Sequence? | One suit? | Result |
|---|---|---|---|
| 5♣ 6♣ 7♣ 8♣ 9♣ | Yes | Yes | Straight flush |
| 5♣ 6♦ 7♣ 8♣ 9♣ | Yes | No | Straight only |
| 2♥ 5♥ 8♥ J♥ K♥ | No | Yes | Flush only |
| 6♠ 7♠ 8♠ 9♠ J♠ | No; 10 is missing | Yes | Flush, not straight flush |
“Almost” does not qualify. Four cards in sequence and suit are a draw, not a completed straight flush, unless a separate bonus explicitly pays for that draw.
The royal flush is the top end of the category
A royal flush is 10–J–Q–K–A in one suit. Structurally it is an ace-high straight flush. Many poker rules name it separately, and video poker paytables almost always give it a distinct, much larger award.
That separation affects language:
- In a hand-ranking discussion, a royal flush is the highest straight flush.
- In a paytable count, “straight flush” may mean only non-royal straight flushes because the royal has its own line.
- In a progressive side bet, natural and wild royals may be separated again.
Always read the paytable category rather than assuming the same label is used across games.
Ace rules have two ends, not a wraparound
In common five-card high poker, the ace may be high in 10–J–Q–K–A or low in A–2–3–4–5. A suited A–2–3–4–5 is therefore a five-high straight flush, sometimes called a steel wheel.
The ace does not normally wrap through the middle. Q–K–A–2–3 is not a straight, and neither is K–A–2–3–4. Some specialized games can define different sequences, but that exception must appear in their rules.
How rare is a five-card straight flush?
A standard 52-card deck has:
- 10 possible five-card sequences from A–2–3–4–5 through 10–J–Q–K–A;
- 4 suits for each sequence;
- therefore 40 straight flushes when royals are included.
The number of unordered five-card hands is:
\binom{52}{5}=2,598,960So the probability of a random five-card hand being any straight flush, including a royal, is:
P=\frac{40}{2,598,960}\approx0.001539\%That is about 1 in 64,974 random five-card hands.
If a paytable separates the four royal flushes, 36 non-royal straight flush combinations remain:
P(\text{non-royal})=\frac{36}{2,598,960}\approx0.001385\%These figures describe a fresh random five-card deal. They are not the final-hand frequency for optimally played video poker, where the player holds some cards and replaces others according to strategy.
A video poker draw has a different calculation
Suppose a player is dealt 5♠–6♠–7♠–8♠ plus an unrelated card in a game without wild cards. After holding the four suited consecutive cards, 47 unseen cards remain. The 4♠ and 9♠ complete a straight flush, so the direct completion probability is:
P(\text{complete})=\frac{2}{47}\approx4.26\%For a one-ended holding such as A♦–2♦–3♦–4♦, only the 5♦ completes the straight flush, giving 1/47, or about 2.13%.
Those percentages do not by themselves decide the correct hold. The discarded cards, paytable, royal possibilities, ordinary flushes, straights, high pairs, and other paying outcomes all contribute to expected value. The strategy chart or a verified video poker analyzer compares the complete outcome tree.
Natural and wild straight flushes may be valued differently
In Deuces Wild or Joker Poker, a wild card can stand for a missing rank and suit. A hand such as 5♥–6♥–7♥–8♥–2♣ may be evaluated as a straight flush if the deuce is wild and represents 9♥ or 4♥.
The machine awards the highest category allowed by its rules. Some paytables distinguish a natural royal from a wild royal but combine natural and wild ordinary straight flushes. Others use different categories. Loto-Québec’s published video poker rules define straight flush and royal flush separately, illustrating why the displayed schedule controls the award.
The same words can describe different hand sizes
Casino poker variants adapt the category to their card count:
- Three Card Poker and blackjack side bets may use a three-card straight flush.
- Four Card Poker uses four-card hand categories.
- Standard draw poker, video poker, and many hold’em-derived bonus wagers use five cards.
- Pai gow poker progressives can define five-card or seven-card straight flush awards.
Massachusetts’ published poker rules provide examples of both five-card and three-card straight-flush definitions. This is why “five cards in sequence and suit” is accurate for standard poker but not a universal casino definition.
Comparing two straight flushes
When two players have straight flushes of the same required length, the hand with the higher top rank normally wins. A 9-high straight flush beats an 8-high straight flush. The wheel A–2–3–4–5 is five-high, so it loses to 2–3–4–5–6. Suits generally do not break ties in standard poker; two identical-rank straight flushes formed from shared community cards split the pot unless the game rules say otherwise.
Casino bonus wagers can use a different settlement method. A paytable may award a fixed amount for any qualifying straight flush instead of comparing it with another player’s hand. The hand-ranking question and the wager-settlement question must therefore be kept separate.
Ranking and payout are separate questions
A straight flush normally ranks above four of a kind in standard five-card high poker. The amount paid is a different matter. A video poker machine can pay 50 credits per credit bet for a straight flush, a side bet may post 40 to 1, and a progressive game may award a meter percentage. None of those payout examples changes the hand definition.
For the surrounding categories, compare straight, flush, and royal flush. For machine-specific value, the paytable is the final authority.
A straight flush is easy to recognize once the two tests are kept separate: every required rank must connect, and every card must share the suit. The game then decides how many cards are required, whether wild cards qualify, and what the completed hand pays.