What is a Straight Flush? Everything you Need to Know

Geoff Fisk
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Last updated: July 11, 2022 4:00 pm EDT

The Poker.org poker hands charts and rankings series defines each variety of made hands possible in a game of poker. This article delves into the straight flush, one of the best hands you can possibly make.

Examples of straight flushes include hands like JT987, 9♣8♣7♣6♣5♣, and A♠2♠3♠4♠5♠.

Introduction

Making a straight flush gives you one of the strongest hands on the poker hand rankings chart. Straight flushes stand as the second-highest ranking hand in poker, only losing to royal flushes.

Besides the royal flush, all other hands lose to a straight flush. This hand consists of five consecutive cards, all of the same suit.

The royal flush is actually just the highest possible straight flush, consisting of a ten-to-ace straight of the same suit. All other occurrences of making five sequential cards, all the same suit, fall under the category of a straight flush.

The straight flush explained

A straight flush essentially represents a hand that makes a flush and a straight at the same time. Flushes and straights are both relatively tough to make in a poker game, but making a straight flush marks an exceedingly rare occurrence.

You must put together five sequential cards of the same suit to make a straight flush. For example, a hand like JT987 would qualify as both a flush and a straight, but the rare incidence of both at the same time makes this hand a jack-high straight flush.

A♠2♠3♠4♠5♠ marks the lowest-ranking straight flush, while K♣Q♣J♣T♣9♣ represents the highest-ranking straight flush.

The suits themselves don’t affect the strength of a straight flush. For example, A♠2♠3♠4♠5♠ is the same as A2345.

What beats a straight flush?

Only a royal flush beats a straight flush, according to the standard poker hand rankings. A royal flush is actually the best possible version of a straight flush.

For example, a hand like A♣K♣Q♣J♣T♣ qualifies as a royal flush and would beat any straight flush. Note that the ace can act as both the high card of an ace-to-ten royal flush and the low card of an ace-to-five straight flush.

In a battle of two or more straight flushes, the hand with the highest-ranking high card wins. For example, K♣Q♣J♣T♣9♣ (king-high straight flush) beats J♣T♣9♣8♣7♣ (jack-high straight flush).

Does a straight flush beat four of a kind?     

Yes. A straight flush beats four of a kind and all other hands below that in the poker hand rankings. The straight flush stands as the second-highest hand in the poker hand rankings, while four of a kind represents the third-highest hand.

Does a straight flush beat a full house?

Yes. Only the royal flush beats the straight flush, and the straight flush defeats all other made hands in the poker hand rankings. 

Full houses, while very strong, lose to straight flushes in a head-to-head battle at showdown. Even the strongest possible full house loses to any straight flush.

What is the probability of getting a straight flush? 

There are nine different possible straight flush hands for each suit, not counting the royal flush. With four suits in a deck of playing cards, there are 36 possible straight flushes you can achieve. Since there are 2,598,960 potential hands poker players can draw when playing with a standard 52-card deck, you can calculate the probability of getting a straight flush as 36/2,598,960.

If you drew five random cards out of a regulation 52-card poker deck, you’d have only a 0.00139% probability of making a straight flush (excluding royal flushes). That probability translates to 72,192.3-to-1 odds against drawing a straight flush.

Texas Hold’em poker probabilities calculate the chances of making a five-card hand out of seven total cards. With all five community cards on the board, you have a 0.0279% chance of making a straight flush (excluding royal flushes) in a game of Texas Hold’em.

That’s a little better than your chances of drawing a five-card random straight flush, but the odds against making a straight flush in Texas Hold’em are still 3,589.6-to-1.

Those odds are also considerably better than achieving the best possible hand of a royal flush (30,939-to-1), but if you do get a straight flush, you should definitely consider yourself lucky!

What is a flush draw?

In poker games, a draw is when you’re one or two cards away from a ranking hand, so a flush draw is when you’re one card short of having a straight flush. The most common type of flush draw is when you have four consecutive cards of the same suit.

An example of a four-in-a-row flush draw would be 6♠7♠8♠9♠. Your hand contains four consecutive spades cards and you just need either the 5♠ or the T♠ to get your straight flush.

Another potential flush draw would be if you had two sets of connected cards (6♣7♣ and 9♣T♣) and just needed the middle card (8♣) to finish out your straight flush.

Straight flush vs. straight flush

In the rare event that two or more straight flushes face each other at showdown, the hand with the strongest high card wins. For instance, K♣Q♣J♣T♣9♣ (a king-high straight flush) beats J♣T♣9♣8♣7 (a jack-high straight flush).

The ace-to-five straight flush (A♠2♠3♠4♠5♠) is the lowest possible straight flush (five-high), and the nine-to-king straight flush (K♣Q♣J♣T♣9♣) is the strongest (king-high).

How to play a straight flush in Texas Hold’em?

If you’re playing a Texas Hold’em variant and you want to get a straight flush, you have a different set of probabilities to consider.

If you’re dealt suited hole cards (two cards of the same suit like 6♣T♣) or two suited connected cards (two consecutive cards of the same suit like 6♣7♣), then your probability of getting a straight flush on the flop is extremely slim (0.0012%). 

In the case of suited hole cards, you would need the community cards to be your missing cards exactly (7♣8♣9♣). With suited connected cards, you have a bit more flexibility because you could make a straight flush with lower cards (3♣4♣5♣), higher cards (8♣9♣T♣), or a combination of the two. In both situations, getting a straight flush on the flop isn’t impossible, but it is unlikely.

Your odds of getting a straight flush on the turn with two suited cards increase to 4.25%. Getting a straight flush on the river is just a little more likely at 4.35%.

It’s always preferable to build a straight flush with both of your hole cards instead of just one. Otherwise, the community cards would include four consecutive suited cards and it’s more likely that another player may also use them to make a straight flush.

Examples of a straight flush

Any hand consisting of five consecutive cards of the same suit qualifies as a straight flush. Hands like K♣Q♣J♣T♣9♣ (king-high straight flush), JT987 (jack-high straight flush), 9♣8♣7♣6♣5♣ (nine-high straight flush) and A♠2♠3♠4♠5♠ (five-high straight flush) are all examples of straight flushes.

Note that the royal flush (A♣K♣Q♣J♣T♣) is the best possible straight flush but gets ranked in its own category as the strongest possible hand you can make in a game of poker. 

The ace can act as the low end of the ace-to-five straight flush (A♠2♠3♠4♠5♠), but the ten-to-ace straight flush (A♣K♣Q♣J♣T♣) qualifies as a royal flush.

The takeaway

Whether you’re playing a five-card-draw online poker game or other popular card games like Omaha or Texas Hold’em, a straight flush is the second strongest poker hand you can achieve.

Every poker player hopes to take the pot with an impressive royal straight flush, but working towards any type of straight flush is a worthwhile goal. 

If you find yourself with a flush draw with low cards, it’s important to remember that you can still lose to a higher ranking straight flush, but if you have a king-high straight flush or a queen-high straight flush, then you can feel confident about placing higher bets.

Featured image source: Flickr by Guts Gaming used under CC license