Omaha 8 (or "O8") is a fun flop game which shares a lot of key characteristics with Hold'Em, but is defined by where it deviates. In a game of Omaha you get dealt four cards, and at showdown you must you exactly two from your hand and three from the board. And in a game of Omaha 8 (where the 8 stands for 8-or-better) the pot sometimes gets split between two winners (or even more!)—the Hi hand winner and the lo hand winner. This page is specific to helping folks figure out who wins the Lo side of the pot.
Even among experienced poker players, trying to determine the winner for the lo side of an O8 pot can take a few minutes. Because it frustrates me that figuring out a winner for a pot (even if only for half the pot) can take me so long, I wanted to see if I couldn't put a framework around the idea to help speed things along. And once I had arrived on a simplification that I liked, I though it'd be wise to share among our poker crew. I know that a simple write up on a simple web page is not going to eliminate the delay caused at O8 showdowns, but hopefully it helps speed things a bit along (or help folks feel more comfortable with what is a very fun game). Or maybe you just find it interesting to turn the chaotic into something a bit more organized.
Anyway, in the hopes of creating a framework which would stick with folks at the poker table, I created a system based around going to the P.U.B. Is a Lo Possible, is your hand sufficiently Unique, and which Lo hand is Best?
Because of the showdown rules of O8 there are two distinct criteria which must be met for there to even be the Possibility of splitting the pot between the Hi and Lo hands. First up, when you look at your hole cards, you must have at least two unique ranks which are Lo-eligible (8 or less). Secondly, by the time all the community cards have been revealed, there must be at least three unique ranks among them which are Lo-eligible.
You're the only person (hopefully) who can see your hole cards, so only you can evaluate the first criterion. But depending on the poker crew you're playing with, there may be some running commentary about the board and whether or not there would possibly be a split pot including the Lo hand. Such commentary is generally not acceptable (or even explicitly disallowed in the rule set) at the poker table, but each group has its own level of permissiveness. Still, you're now armed with the knowledge as to what makes a Lo split possible.
If these conditions aren't true (for your hand or for the board), then neither of the next two sections will come into play.
First up, for here on out every time I refer to an "eligible card" (be it in your hand or part of the community cards), I mean cards ranked 8 or lower of unique rank. If you were dealt an O8 hand consisting of A66J, I'd say you have two eligible cards in your hand (an ace and a six). If the flop is 229, then there are one (Lo) eligible cards on the flop (a single deuce). In fact unless I explicitly state otherwise, you can assume that from here on out on this page, every time I refer to a card, I specifically mean a Lo-eligible card. If I keep typing "unique rank not including 9, T, J, Q, or K" then there are going to be a lot of extra words on this page.
Please re-read that previous paragraph. It's vitally important for your understanding of the rest of this page.
So how do you determine whether your hand is sufficiently Unique to stake a claim for the Lo side of the pot? Well by the end, between your hand and the board, you need a 5 card hand with two cards from your hole cards, and three cards from the board. That sounds really simple to determine, but if you've spent any time sitting and playing O8, you know that sometimes its trickier to figure out than you think.
As long as you have at least two cards in your hand, then the real way to think about your eligibility for a Lo is based on the board texture at showdown based on one of these three categories: A) the board has three cards, B) the board has four cards, or C) the board has five cards.
If the board has three cards, then your eligibility is predicated on you holding (at least) two Unique ranks compared to the board.
If the board has four cards, then you're eligible for the Lo if you have (at least) one Unique rank compared to the board.
And if the board has five cards, then you are to be eligible to stake a claim for the Lo side of the pot.
Note well, these three sentences are ONLY true if the conditions of the Possible requirement (in the section above this one) have been met.
This is where the vast majority of discussion and debate occurs when folks attempt to discern who wins the Lo pot. If you have exactly two cards in your hand and there are exactly three cards on the board, then this is a pretty straightforward thing to figure out. However, when you've got three cards in your hand, and there are four or five cards on the board and there's some rank overlap between the two... well it can end up stymieing the most resolute of O8 players.
I created a 3 × 3 matrix of possibilities (the players has 2, 3, or 4 cards; the board has 3, 4, or 5 cards) and considered everything from every angle to create a detailed process to determine the lo winner in each case. I'll spell that out here, actually, but then in the next section I'll conceptualize what this actually means and in the last section I'll write up some generalities which may be easier to remember when you're actually at the table—especially after you join me on my tour through my own process.
The board has three cards:
whomever has the lowest two unique ranks (as measured by the higher of the two hole cards) wins the lo pot.
In the 3-card board case, it's also acceptable (especially based on how the betting goes) to identify the nuts based on the board, and then go looking for it in players' hands. This won't always work, but it works often enough to dispense with this particular process. This also works in theory for the 4-card and 5-card board conditions, but for these cases, especially if the cards making up the board are exceptionally low (5, 4, 3, 2, and A), there may be many 2-card hand permutations that make up the nuts.
The board has four cards:
whomever holds the lowest two unique ranks smaller than the 3rd highest board card wins the lo pot, or
whomever holds the two lowest unique hole cards below the rank of the 4th highest board card wins the lo pot (again as judged by the higher of the used unique ranks), or
whomever holds the lowest unique hole card and one repeated rank with the board both of which are below the rank of the 4th highest board card wins the lo pot, or
whomever holds the lowest unique rank wins the lo pot.
That algorithm is actually not fully airtight, but by the time you get to the end of this page these specific steps are not going to be what you end up remembering, so I won't bore you with the super edge-cases.
The board has five cards:
whomever holds the lowest two unique ranks smaller than the 3rd highest board card wins the lo pot, or
whomever holds the two lowest unique hole cards below the rank of the 4th highest board card wins the lo pot (again as judged by the higher of the used unique ranks), or
whomever holds the lowest unique hole card and one repeated rank with the board both of which are below the rank of the 4th highest board card wins the lo pot, or
whomever holds the two lowest unique hole cards below the rank of the 5th highest board card wins the lo pot (again as judged by the higher of the used unique ranks), or
whomever holds the lowest unique hole card and one repeated rank with the board both of which are below the rank of the 5th highest board card wins the lo pot, or
whomever holds the lowest unique rank wins the lo pot.
(Of course, I didn't actually get this far when explicitly figuring out winners, as the pattern had begun to present itself to me, so maybe those six sentences don't actually make any sense whatsoever...) Keep reading, please.
Concept
So the pattern which presented itself was that we're really trying to see how our cards fit within the board. The best case scenario is that your five-card hand has the 3rd highest board card as its worst rank. I.e., the board reads xx752, your best scenarios is for your hole cards to be unique and below the 8:
3-Card Board: 752
Best: 7[52
You want your cards to fit below the red bracket (i.e., less than the 7 and not a 5 or 2—so one combination of 3A, 4A, 43, 6A, 63, and 64)
The next best possibility would be:
2nd Tier: [752
Which means the worst unique hole card you're using was an 8 and the other unique card was a 6, 4, 3, or A. Note that these tiers correspond to the number system I used above in explicitly designating hand possibilities from best to worst.
The 3-card board is pretty simple. But how does this look for a 4-Card Board? We'll use x864A as our example:
4-Card Board: 753A
Best: 75[3A
Again, our best scenario is that we use the 3rd highest card on the board as the worst card in our 5-card hand. To fit in this best category we need two unique cards lower than the third-highest card (only the 42).
The next tier looks familiar as well:
2nd Tier: 7[53A
In this case our "defining card" (unique card in our hand that won't allow us to use the 5 as the worst of your 5-card hand) has to be a 6, and its partner a 4 or 2.
But what of the next best possibility?
3rd Tier: 7[53A
The underline indicates that you could repeat one of these three cards in your hand, and the square bracket shows that you also want a unique rank falling in this range. If, for instance you held a 6A in your hand, then you've got a five card hand that looks like 7653A. And if you were up against someone who held a 54, then they fall in this same tier, but they have an 7543A. And since their unique card (the 4) was better than your unique card (your 6), they have a lower lo and would win the pot.
Finally we have the bottom-most tier:
4th Tier: [753A
This indicates that we've got one unique rank specifically not falling below the 4th card, and any repeated card. Based on our example, the only hole cards which fit would be the 87, 85, 83, and 8A, and since they all have the same unique card (the 8), they all have an equal claim to the lo pot (in each case the resulting low hand is 8753A).
Let's finish the progression with a 5-card board example:
5-Card Board: 7532A
Best: 753[2A
Based on my construction of the example, there are no hands which fit into the best category (two not-already-present-on-the-board cards lower than the third-highest board card, the 3). Next tier:
2nd Tier: 75[32A
Again we're left with an impossible criterion, there are no two unique cards in a hand which are lower than a 5 and not already appearing on the board.
3rd Tier: 75[32A
Here we've finally found hands which fit the progression. We need one unique rank below the fourth-highest board card and any other card which matches the rank of one of these family of board cards. Specifically we could have a 4A, 42, or 43 to fit, and in each case the unique card (the 4) is the same, so they're all the same low hand: 5432A.
4th Tier: 7[532A
Here we want two unique cards lower than the 5th highest board card, and we're only left with exactly 64, which gives you a hand of 6432A.
5th Tier: 7[532A
At this tier, we're after a unique card below the fifth-highest board card and a card which matches a board card. This can be any of 6A, 62, 63, or 65 (and results in a low of 6532A.
Tiers 6 and 7 use the same pattern we've seen for tiers 2-5:
6th Tier: [7532A
7th Tier: [7532A
For this example, these are both hands that start with an 8 (6th Tier: 84, 86; 7th Tier: 8A, 82, 83, 85, or 87).
And very specifically to the 5-card board condition, there is one final Tier:
8th Tier: 7532A
This indicates that you hold no unique cards in your hand, and that you are, in essence, "playing the board" (though obviously to get passed the P section near the top of this page, you had to have at least two unique eligible cards in your hand). You have a hand eligible to win the lo pot, but it doesn't beat any other lo-eligible hands.
The generality of who wins a low depends on what tier they fall in. And Tiers are defined by how unique your hole cards are, and how they compare to the 3rd, 4th, or 5th highest card on the board.
The super-general tiers of hands then, would be:
Two unique hole cards below the 3rd best board card
Two unique below the 4th best board card (change this to "below a 9" in the case of not having at least 4 eligible board cards)
Two cards at or below the 4th best board card (one must be unique from the board) in order of the unique card
Two unique cards below the 5th best board card
Two repeating cards on a 5-card board
If the board reads 8642 then the order of winners would be:
3A, 5A, 53 (these would make, in order, 6432A, 6542A, and 65432)
7A, 73, 75 (these would make 7642A, 76432, 76542)
8A, 83, 85, [72 | 74 | 76 | 87] (these make 8642A, 86432, 86542, and {four ways} 87642)
Tier 3 maybe should read "at or below the 4th highest card" as you could repeat the 4th highest card but have a low unique, and that'd be better than a repeater and a bad unique. Looks like this persists in the text and in the graphical examples.