ICM, and Its Impact on Tournaments

ICM stands for Independent Chip Model. Essentially, this is a mathematical model that calculates a player’s equity in a tournament given their chip stack, other player’s chip stacks, and the payouts. ICM doesn’t have a significant enough effect to come into play until we are near or in the money and has its most pronounced effects when there are large pay jumps looming, such as on the bubble or at the final table of tournaments.

This page will take you through all aspects of ICM poker, from explaining the concept to showing you when and how to use ICM poker strategy.

What is ICM in poker?

Independent Chip Model, known as ICM, is a model that shows you the real equity value of your stack rather than the chip value. It does not apply in cash games, because the cash value of chips is completely linear.

In tournaments, the equity value of chips fluctuates because the payouts are tiered. You can’t cash out your chips, so your stack is only ever worth the same as your combined chances to win each prize.

ICM tools calculate each player’s equity share of the prize pool based on their current stacks and the payout structure. The calculation doesn’t take into account factors like skill level or who has position. It is a cold, hard calculation based only on stacks.

The ICM calculation is too complex and never performed manually by humans. It runs thousands of simulations. Floor staff use ICM tools to formulate deals in tournaments, while players use ICM tools to perform calculations when they are analyzing spots in which it is a significant factor.

If you’re into the maths and want to perform these calculations for yourself, we recommend an ICM calculator like ICMIZER to run your spots. Even without doing that, we can look at ICM in action and understand its impact on poker strategy.

Why is ICM Only Relevant in Poker Tournaments?

In cash games, a $1 chip equals $1. If there is a 10-handed table and everyone buys in for $100 and someone won all those chips, they would have $1,000 in real money (minus the rake). If a player exactly doubled up, their stack would be worth $200. The value of the chips in play never fluctuates.

In a tournament that’s not the case, however. In line with the 10 handed cash game example above, let’s change it to a one-table table tournament, a sit and go with a $100 buy-in.

Between the ten entrants, there is still $1,000 in real money in the pot. But now, whoever wins all the chips does not have $1,000 in real money. With a payout structure that awards 50 percent to first place, the winner would take $500. The other 50 percent of the money would be split between other finishers, such as 30 percent to second and 20 percent to third place.

Everyone gets this. What this means though, is when we are faced with ICM decisions in tournaments, the chips we can gain from taking a risk aren’t worth as much as the chips we may stand to lose from that play. Losing chips reduces the chances of making the higher positions, while winning the same amount of chips wouldn’t make up for that risk.

ICM impacts the game in a very slight way from the beginning. But there are certain times in poker tournaments when ICM becomes a huge factor and can even lead to players correctly folding monster hands, which we’ll explore soon. First though, let’s grasp the implications of ICM in tournament poker.

Implications of ICM in Poker

Here are the key implications of ICM when playing tournament poker:

• Chip versus cash value: Unlike in cash games, each chip has a diminishing value in a poker tournament. This is the core principle of ICM. It encourages survival over chip accumulation, especially during key moments in the game.
• Risk management – In ICM heavy spots, you’ll need to mitigate risk by avoiding marginal confrontations that can cost your entire stack or put you at risk of missing out on pay jumps. Folding can make you money when ICM is a factor.
• Stack sizes – How you navigate ICM spots will depend on your stack size. Big stacks have the advantage, while medium and short stacks have an incentive to tighten up.
• ICM punishes calls – ICM punishes bad and marginal calls more than shoves. When you are shoving, you generate fold equity against opponents who are also trying to survive. Calling in marginal spots is a disaster when ICM is involved and sometimes you can even justify folding when you are ahead.

ICM-Heavy Spots

Although ICM is technically always a factor in poker tournaments, it only really becomes a significant enough factor to influence decisions during certain key moments during the game, such as when the bubble is approaching or on the final table when pay jumps are huge.

The exact curve of ICM’s influence starts off tiny, then very gradually rises as the money gets nearer. It then shoots up near the bubble, then drops off again dramatically once the money is reached. This is because pay jumps tend to be very small until later on. ICM then becomes a huge factor again as the final table approaches and on the final table as pay jumps become significant and remains a huge factor until action is heads-up. Once a tournament is heads-up, there is absolutely no ICM involved in decisions.

So, for the sake of poker strategy, the main times when you need to consider the implications of ICM described above are the bubble and final table.

ICM on the Bubble

ICM hits its first peak as the bubble approaches, especially when there are only one or a few players left to bust before making the money. At this point, losing your stack would be tragic, especially if you have a medium or big stack that would have survived without needing to take risks.

The priority on the bubble becomes survival. This is particularly relevant for medium stacks and short stacks who still have a chance to make it through without having to punt. First, you want to make it through into the money. Then you can take risks.

Pay jumps

ICM slackens off after the bubble has burst. It’s still a minor factor in that losing chips is still slightly worse than the advantages of winning chips. But for practical purposes, ICM only starts to rear its head again as the pay jumps start to become big. In an MTT, this happens as the final table approaches and particularly on the final table.

The greater the number of people on the final table, the more ICM pressure is at work. This is because there’s more chance someone else will bust before you when you have a medium stack and there are nine players left. In any case, moving up the ladder through pay jumps without having to take risks yourself is a winning ICM strategy. Again, it’s all about survival now and taking risks later.

Satellite bubbles

Satellite bubbles have the most ICM out of any tournament because they have a completely flat payout structure. If 10 players make the money and 11 players are remaining, you only need one person to bust before you. There’s no benefit to accumulating chips in a satellite if you are already guaranteed to win the prize.

The ICM becomes such a big factor on satellite bubbles that it can become correct to fold pocket pairs as high as kings or aces to a shove or even to open-fold premium hands. It’s simply not worth getting involved. The ICM spike is so high that the chance of winning chips can never outweigh the risk of losing, even if you have loads of equity.

ICM Example

An easy way to see this is to use a contrived extreme example. Let’s say it’s the bubble of a sit and go, four players remain and it pays $500, $300, and $200 respectively for the top three. Let’s say the blinds are 200/400 and the stacks are like this:

Hero: Big Blind 7,000
Player 2: Small Blind 7,998
Player 3: 1,000
Player 4: 1,000

In this example, Player 3 and Player 4 are going to be forced to make a move soon, or else be blinded out during the next orbit. By allowing them to bust first, the Hero is almost guaranteed second place prize money. They will then face Player 2 in a near-even heads-up battle for first place. This is the ideal and most likely scenario if nobody makes any dramatic moves.

Now, let’s say that the action folds around to the small blind, who moves all in for a little under 20 big blinds. This is a clear ICM fold with nearly every hand, certainly ace-king, and you could even argue for folding out premium pairs.

Do you see why? If you play this hand and win, you’ll have all but locked up the SNG. Your equity in the game would be huge after near-doubling your stack and leaving Player 2 short. You’re still not guaranteed a win, as other players could rally, but you’re not far from it. However, if you call Player 2’s hand and lose, your equity is reduced to zero and you win $0.

This is a pure ICM disaster, because by simply folding, you’ve essentially got second place locked up and a good chance to take first place.

So, if you call and win, you’ve only increased your equity in the prize pool nominally, while if you call and lose, you’ve forfeited all equity and walk away with nothing. The risk is enormous for a reward that’s not often worth it in terms of cash equity. Thus, the correct play, the one that maximizes your earn in the long run, is to fold most hands against Player 2 until Player 3 and 4 bust.

H2: ICM vs Chip EV

When ICM is not much of a factor, you’ll be playing purely for chip accumulation. This will always be the case in a cash game and will also be the case in the early stages of poker tournaments as well as when the bubble has just burst.

During times when ICM is not worth considering, stick to chip EV decisions. In other words, you should weigh up what actions to make based on your will gain more chips than you will lose in the long run.

When playing chip EV poker, you can technically take marginal spots profitably, as any edge will accumulate in the long run. Still, you’ll want to be ahead of your opponent’s range and have more equity than they do in the pot.

As ICM comes into play, you should start to deviate slightly from the optimal chip EV solution, tightening up to account for ICM, particularly when it comes to calling raises or shove that can damage your chances of making the money or laddering up.

Calling off chips is the biggest ICM mistake you can make, particularly if you only have 50-60 percent equity against your opponent’s range. The chip EV gains are not worth the ICM losses. To make a call in an ICM heavy situation, you’ll often need 80 percent equity or better to make the chip EV gains worth the risk.

As you can see, ICM has a dramatic impact on poker strategy. When it is not significant, you should be playing chip EV poker with the aim of growing your stack. At ICM pressure points like the bubble or pay jumps, ICM overrules chip equity by quite a margin.

H2: Key Factors That Affect ICM Decisions

Aside from the situation itself bringing with it ICM pressure, here are the other key factors that affect ICM decisions:

• Stack sizes relative to others – Your stack size relative to your opponent gives an indication of where you are in terms of your chances of a top place finish. It also impacts how you play during key ICM moments. We’ll cover ICM by stack size in full soon.
• Payout structure – Smaller pay jumps have way less ICM at work and so you should still focus on chip accumulation. It’s only during the bubble, which is an all or nothing payout, and during bigger prize jumps, that ICM is a significant factor.
• Number of players left – The more players left when pay jumps are big, the more ICM becomes a factor because there’s more chance others will bust before you so that you can ladder up. It’s not worth taking huge risks when several players are likely to bust.
• Calling versus shoving – You don’t want to be the one calling in an ICM spot, as this means you’ll have to run your hand purely off equity. Given that you won’t have enough equity to make it worthwhile, calling light is not an option. Shoving, on the other hand, generates a huge amount of fold equity.
• Being at risk – Calling off a small amount of your stack may not be too bad if you can still remain ahead of the pack and in with a chance of making the money. It’s situations that put you at risk that you should avoid when ICM is heavy, such as calling all-in with a coinflip.

ICM Strategy Adjustments by Stack Size

In ICM heavy situations like the bubble or before big pay jumps, you should adjust your strategy based on your stack size. In this context, your stack size is not only measured according to big blinds, but also in comparison to other players’ stacks who are still in the game. If several other players are shorter than you and under pressure from the blinds, it’s likely one of them will bust first even if you also have a short stack.

Here’s a quick guide that will help you to navigate ICM decisions based on your stack size:

Short stack (at risk) – With a short stack that is at risk from the blinds or is one of the shortest at the tables, it’s important that you continue to make shoves to stay ahead of the blinds, preferably while you still have fold equity. You’re still looking to survive, but your path to doing that involves either stealing blinds or doubling up. You likely won’t survive by waiting around.

Short stack (others shorter) – If you have a short stack in terms of number of blinds, but other players are even shorter, you’ll still want to take huge equity spots with big hands as well as very profitable shoves. However, you’ll start to tighten up, especially when it comes to calling, as it’s likely other players will bust first. You can take risks again once the bubble has burst or pay jump has been made.

Medium stack – Medium stacks have the most to lose from heavy ICM situations. The risk of busting now is too great and would be very costly, as medium stacks can nearly always make it through the bubble with no further action. That doesn’t mean you should sit out, but you’ll certainly be incentivised to tighten up both shoving and calling ranges, especially against opponents who have you covered. You can still shove on short stacks in decent spots.

Big Stack – Having a big stack in a high ICM situation like the bubble is an absolute dream. You’re almost guaranteed to make it through and very few players will be able to put you at risk. Use pot control against other big stacks, while rampaging over short and medium stacks who are correctly trying to survive. Raise often preflop, steal blinds, make small c-bets, and take other low risk moves to accumulate chips ready for the later stages.

ICM in Action – Folding Aces

Written by (Person) about their own  experiences in (Year):

The effect of ICM leads to some very counter-intuitive shoves or folds late in key ICM spots such as the final table or bubble, especially on the bubble of satellites. I recently had an extreme example of this occur to me, where I folded AA before the flop live on stream while the chat went wild.

Here was the situation. It was a satellite on the stone bubble with four tickets to the target event, on the direct bubble with five players left. The blinds were 2000/4000 with a 400 ante. The stacks to start the hand were:

UTG: 26,052
CO: 60,016
BU (Hero): 14,773
SB: 13,640
BB: 137,519

UTG raises all in for 25,652
CO re-raises all in for 59,616

In this scenario, where the stack in third place is at immediate risk of busting out, it is the correct ICM play for us to fold all hands, including AA. If you run this through an ICM calculator, you’ll see this to be true:

This is, quite simply, because my equity in this satellite prize pool (my chance to get one of the four tickets to the target event), goes up if I fold AA versus if I call with it in this situation.

Other interesting notes from this ICM run… the cutoff, who re-jammed, is actually only supposed to do this with AA/KK. Why so tight? Intuitively, if the cutoff loses this confrontation, they will have 8.5 bigs left and be in third. If myself and the small blind win our next all ins, they will be the shortest stack. Also, the cutoff could be at risk right now to the big blind who still hasn’t acted yet.

Whether or not this sounds too tight, re-shoving with QQ here slightly decreases his chances of winning a ticket versus if he simply folded, another counter-intuitive result of ICM. By the way, if we edit the re-shove range of the cutoff to include QQ and AK, we still have a very clear fold with the AA versus the two all-ins.

Another interesting point to look at here… when the UTG player jammed, I said on stream “well, I have to call him obviously” just before the cut off re-jammed. Is this correct, and if so, how wide should I be calling? Yes, it’s correct, I should call the UTG player’s shove if everyone else folded. But I should be calling his shove very tight even against just their range.

So had the cutoff folded, my AA is a snap call, KK is only marginally profitable and anything else loses money/equity and reduces my chance to win a ticket (because I will be at risk right now). Had you asked me on stream how wide I would have called the UTG shove if the cut off folded, I would have said JJ+/AK. As the true ICM calculation illustrated, calling off with JJ would be lighting money on fire.

The moral of this story is, ICM pressure is a very real factor in poker tournaments. It’s often better to be the one shoving rather than calling off in the face of ICM pressure. These effects are more pronounced the bigger the pay jumps, like what occurs at the final table of tournaments or the direct bubble of a satellite.

Getting your head around these concepts, at the very least in a basic sense, will help improve your decision making deep in tournaments or satellites, leading to more long-term profit while your less savvy opponents make huge ICM mistakes and blow up their equity.

Common ICM Mistakes in Poker

ICM is a difficult concept to fully understand, nearly impossible to calculate without a software tool, and some of its implications are counter-intuitive. As you can imagine, there are multiple common mistakes that players tend to make when it comes to ICM in poker:

• Calling too wide – One of the biggest ICM leaks players make is to ignore ICM or overvalue their hand strength when making big calls. As demonstrated, you need lots of equity to justify calling shoves on the bubble. ICM spots are not the time for calling light, especially if the call puts you at risk or drastically reduces your stack.
• Ignoring stack sizes – The way you should adapt your poker strategy in ICM situations depends almost entirely on your stack size in relation to other player’s stacks. Failing to recognize your position in the tournament is a big mistake. You should always be adapting based on stack sizes and keeping an eye on short stacks who are likely to bust.
• Not playing for pay jumps – Poker players used to have a play to win mentality, but now the role of ICM is widely acknowledged. Pay jumps really do matter and ignoring them is a huge error that will cost you a lot of equity. Consider pay jumps when they are significant, such as on the final table.
• Overfolding big stack – As a big stack, you can and should apply a huge amount of ICM pressure to shorter stacks who are looking to survive. If you play passive on the bubble with a big stack or fail to push around opponents on the final table, you’ll miss out on loads of spots to gain chips without much push back.
• Satellites – Playing satellites like they are normal tournaments is a huge mistake. ICM is at its most extreme on the bubble of satellites. You shouldn’t be making huge calls on the bubble of a satellite when you can make it through without risk, even if you have a hand like pocket jacks or ace-king.