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. Both hands are dealt face down; you look at yours, and the dealer’s stays hidden.
- 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. With a two-, three- or four-card flush the raise equals the ante (1x); a five-card flush may raise up to 2x; a six- or seven-card flush up to 3x. Those caps are written into the Maryland, Pennsylvania and Massachusetts rulebooks, and Maryland and Pennsylvania require the table layout to state them.
- 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. These are the only hands allowed to raise more than 1x.
- A four-card flush happens 19.5% of the time — one hand in five. It is beaten on length only about 3.3% of the time, but it ties on length very often, which leaves the result to card ranks.
- A three-card flush is the modal hand at 59%. Most of the time you hold a three-card flush, 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 the maximum every time, without thinking about ranks: 2x with a five-card flush, 3x with six or seven. A five-card flush is longer than the dealer’s best flush in over 96% of deals and a six-card flush in over 99%, so length alone wins the hand overwhelmingly often. The near-optimal strategy published by Wizard of Odds always takes the largest raise allowed.
Four-card flush: always raise 1x
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. There is no sizing decision: a four-card flush may raise only 1x, the same as a three-card flush, so make the 1x raise every time, however low the cards. Ranks still settle the showdown when the dealer also holds four, because the comparison runs card by card from the top, but they do not change what you do.
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 6.2% whose best three-card flush is eight-high or lower — 24.6% in all, comfortably short of that one-third break-even. A weak three-card flush is not quite hopeless (9-8-x beats a dealer who qualifies with 9-6-x), but it wins too rarely against a qualifying dealer to make up the gap. So:
Raise a three-card flush of 10-8-6 or better; fold anything lower. That is Charles Mousseau’s near-optimal rule as published by Wizard of Odds: J-3-2 is a raise, 10-7-5 is a fold, and every nine-high three-card flush folds.
The exact optimum is only slightly finer. Wizard of Odds narrows it to raising J-9-6 or better and folding 9-7-4 or worse, with the hands in between (9-7-5 to J-9-5) left unresolved — and Mousseau’s rule gives up only about 0.06% of the ante against it. Played optimally, you raise about 68% of all hands.
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 several times rarer than the one before it, and the gap widens as the flush grows: 19.5% for four, 2.9% for five (about seven times rarer), 0.2% for six (fourteen times rarer again). 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, from four cards up, 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 of three cards or more. Both are resolved independently of the main hand, and both still pay if you fold it.
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. Maryland’s standard rules alone authorise fifteen Flush Bonus paytables; worked against the exact counts above, their house edges run from 4.05% to 14.22%. The 300-100-10-1 table analysed by Wizard of Odds costs 7.81%, and the Straight Flush Bonus table it analyses (8,000-1,000-100-60-7) about 13.1%. Even the cheapest of those Maryland tables costs more than the main game’s 2.64%.
House edge and honest framing
Played optimally, the Ante/Raise game runs a house edge of 2.64% of the ante (Wizard of Odds), or 1.54% of the average total wager once raises are counted; Mousseau’s simple rule carries 2.71%. That places it among the more reasonable table poker games — below the roughly 3.4% of the ante in three-card poker and above the roughly 2.2% of the ante in Ultimate Texas Hold’em on optimal play. The High Card Flush figures assume the standard rules above: a nine-high qualifier and 1x/2x/3x raise caps.
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.