High Card Flush: Rules, Odds and Strategy
High card flush is a casino table game in which you and the dealer are each dealt seven cards and try to make the longest flush — the most cards of a single suit. Length is compared first, and only when both hands have the same number of suited cards do the card ranks break the tie.
That single rule inverts everything a Hold’em player knows. Five cards of a suit is not a category here, it is a measurement, and a six-card flush of low cards crushes a five-card ace-high flush. Here is the game, the exact probabilities, and where the real decisions live.
How a hand plays out
- Post an Ante. The Flush Bonus and Straight Flush Bonus side bets are optional and independent.
- You and the dealer each receive seven cards. Yours are face up to you; the dealer’s stay down.
- Find your longest flush. Then either fold (losing the ante) or make a Raise.
- The raise you may make is capped by your flush length. Typically: 1x with a three-card flush, up to 2x with a four-card flush, up to 3x with five cards or more. House rules vary — read the layout.
- The dealer reveals. The dealer qualifies with a three-card, nine-high
flush or better.
- Dealer does not qualify: Ante pays 1:1, Raise pushes.
- Dealer qualifies and you win: Ante and Raise both pay 1:1.
- Dealer qualifies and wins: both bets lose. Exact ties push.
The escalating raise cap is the game’s core design: the better your hand, the more of it you are allowed to bet. Everything below follows from working out how often each flush length actually happens.
The exact seven-card odds
These are the real numbers, computed across all 133,784,560 seven-card combinations from a 52-card deck:
| Longest flush | Combinations | Probability |
|---|---|---|
| 7 cards | 6,864 | 0.005% |
| 6 cards | 267,696 | 0.200% |
| 5 cards | 3,814,668 | 2.851% |
| 4 cards | 26,137,540 | 19.537% |
| 3 cards | 78,881,088 | 58.961% |
| 2 cards or fewer | 24,676,704 | 18.445% |
Read that table carefully, because it is the whole strategy in one place:
- A five-card flush or longer happens just 3.06% of the time. When you have one, you are ahead of the dealer’s length in over 96% of hands. This is the maximum-bet hand.
- A four-card flush happens 19.5% of the time — one hand in five. It is beaten on length only 3.06% of the time, but it ties on length very often, which pushes the decision onto card ranks.
- A three-card flush is the modal hand at 59%. Most of the time both you and the dealer are comparing three-card flushes, and the fold decisions live here.
- 18.4% of hands cannot make a three-card flush at all. These are automatic folds.
Basic strategy by flush length
Five cards or longer: raise the maximum
Raise 3x, every time, without thinking about ranks. The dealer holds five or more suited cards only 3.06% of the time, so length alone wins the hand overwhelmingly often. Betting less than the maximum with a five-card flush is the single most expensive error available in this game.
Four-card flush: raise, and size by strength
You cannot fold profitably with four to a suit — you are ahead on length 77% of the time and level on length most of the rest. The question is 1x or 2x. Raise the full 2x when your four-card flush is genuinely high (ace or king high with solid support cards), because the tie-break comparison is card by card from the top and that is where four-card hands are decided. Take the smaller raise with a weak four-card flush headed by a middling card.
Three-card flush: the real fold decision
Here is the piece of arithmetic that resolves it. If your hand is hopeless against any qualifying dealer, folding costs you exactly one ante. Raising 1x wins one ante when the dealer fails to qualify, and loses two units (ante plus raise) when the dealer qualifies. Writing that out, raising only beats folding when the dealer misses the qualifier more than one third of the time.
The dealer fails to qualify on the 18.4% of hands with no three-card flush plus the fraction of three-card flushes below nine-high — comfortably short of that one-third break-even. So:
Fold any three-card flush that cannot beat a qualifying dealer. A three-card flush of nine-high or worse can only tie or lose against a qualifying dealer, so it is playing for a non-qualify that does not arrive often enough.
Above that line, three-card flushes get progressively more playable as the top cards climb, and published optimal charts raise only the strongest of them. Since the exact cutoff depends on your table’s raise rules, use a chart for your specific game if you play regularly. The principle — would this hand beat a dealer who just barely qualifies? — gets you most of the way there on its own.
Why the rankings feel inverted
Hold’em players consistently misplay this game in the same way: they overvalue high cards and undervalue length. In Hold’em a flush is a flush and the ace matters enormously. Here, quantity dominates quality, and it is not close.
The reason is in the odds table above. Each additional suited card is roughly seven times rarer than the one before it: 19.5% for four, 2.9% for five, 0.2% for six. Rank differences within a length class are common and cheap; length differences are rare and decisive. A hand of 2-4-7-9-J in clubs beats A-K-Q-J of spades outright, and that is not a quirk — it reflects how much harder the five-card hand is to make.
The same lesson appears in three-card poker, where a straight beats a flush, and in four card poker, where a flush beats a straight. Rankings are not arbitrary tradition; they follow the frequencies at that hand size. The standard poker hands order is simply the five-card case, and every variant recomputes it.
The side bets
Flush Bonus pays on the length of your longest flush regardless of what the dealer holds, with payouts escalating sharply for six- and seven-card flushes. Straight Flush Bonus does the same for suited runs. Both are resolved independently of the main hand.
Look again at the frequency table before you commit money here. A six-card flush arrives once in roughly 500 hands and a seven-card flush once in about 19,500. The headline payouts exist because the events are genuinely rare, and paytables differ substantially between casinos — a schedule that looks similar at a glance can carry a materially different edge. As with every table-game side bet, expect the house edge to be several times that of the main game.
House edge and honest framing
Played correctly, the Ante/Raise game runs a house edge in the region of 2.5% to 3% of the ante, which places it among the more reasonable table poker games — comparable to three-card poker and a little behind Ultimate Texas Hold’em on optimal play. The exact figure depends on your table’s qualifier and raise rules.
Two points to hold onto:
- Correct play shrinks the edge; it never turns it. High card flush is a house game. No sequence of decisions makes it a long-run winner, and the variance from those rare six- and seven-card flushes can mask that fact for a long time in either direction.
- The main game is the better bet than the bonuses. If you are going to play, keep your money on the Ante/Raise and treat the side bets as entertainment.
Decide your session budget before you sit and treat it as spent. Our responsible gaming page has the practical guardrails. For games where skill actually determines the outcome rather than trimming a fixed edge, the strategy library and the odds calculator are the place to start.
Keep learning: try the free poker odds calculator, memorize the hand rankings, or browse all strategy guides.