Critical Analysis of the 10 BB Shove/Fold Rule
Introduction
In this article
- Disproving an Absolute 10 BB Rule
- Balancing your Min-Raise Range
- Antes and ICM
There is a widely-quoted rule in tournament poker mandating a shove-or-fold strategy with a 10 BB stack. While there is not a single source for this rule, its proponents may express it as:
“With an effective stack of 10 BB or shallower, you should either shove or fold pre-flop, but not limp or make a smaller raise.”
In this article, we will analyze how correct the 10 BB rule is in different situations.
Disproving an Absolute 10 BB Rule
It is not difficult to disprove this rule if we regard it as an absolute.
Those arguing in favor of the 10 BB rule being universally applicable must show that in every instance where the effective stack is 10 BB or shallower, limping or raising smaller are lower EV options compared to folding or shoving. To prove that the rule doesn’t always hold, however, it suffices to give a single counter-example.
Blinds: $50-$100
Our Hand: 
Action: Everyone folds to us on the button. We have a stack of $1,000, as do both blinds. Both blinds have static defense ranges of the top 20% of hands, which they will 3-bet/shove if we raise small, and call if we shove.
Question: Should we fold, min-raise, or shove?
Analysis: Ignoring card removal effects, both players will fold 64% of the time (80% x 80%). If we min-raise, our EV is therefore given by:
EV = Probability (Both Fold) x Reward (Both Fold) + Probability (At Least One Defends) x Reward (At Least One Defends)
= 64% x $150 + 36% x (-$200)
= $24
Now suppose we shove. We win the same $150 64% of the time, but the remaining 36% we are (at best) paying $1,000 for 29.2% equity in a $2100 pot, for a loss of about $387. So the EV of shoving will be at most -$43.32, or lower if the caller is the big blind -- giving us less overlay -- or both call.
The EV of raise/folding a larger amount must also be less than the EV of min-raising, as we simply lose more those times we’re shoved on, but have the same reward for a successful steal.
The EV of folding is $0.
Therefore min-raising is the better play over folding or shoving.
Note that it’s very difficult to calculate the EV of limping due to the number of assumptions involved, but it is likely -EV to voluntarily pay 10% of our stack to get involved against one or two random hands with offsuit low cards.
Lastly, we have assumed in this hand that we are playing a cash game or MTT where we can safely use a chip EV analysis. Later we will see how adding in an ante or ICM framework modifies our results.
The Counter-Argument
A 10 BB rule proponent might object: “You may have shown that given these very specific assumptions, min-raising is the better play for this particular spot. But in the majority of cases, it is still better to shove or fold at this stack depth.”
I wouldn’t necessarily disagree with this last statement. In my early writings, in fact, I advocated shove/folding with 10 BB stacks. One of the initial arguments in favor of shove/fold is that when the effective stack gets that shallow, you’re pot-committed with a smaller raise. With a 10 BB stack, however, that reasoning doesn’t quite hold. If you min-raise and the big blind shoves, the pot will be 12.5 BB, and it costs 8 BB to call. Getting odds of just over 3:2, it is reasonable to fold sometimes.
It isn’t until the effective stack gets down to about 6 BB where any raise commits you. If you min-raise with a 6 BB stack and the big blind shoves, the pot is then 8.5 BB and it costs you 4 BB to call. In that case, you are committed.
So when should you elect to make a small raise short-stacked?
The best players to raise small against with a 7-10 bb stack are tight and predictable opponents who will rarely flat-call with short effective stacks, and will 3-bet shove a similar tight range to the one with which they would have called a shove.
The best players to use shove/fold against are those who will defend widely against small raises. Against such opponents you can still raise smaller, but you must balance your min-raising range, the topic of our next section.
Balancing your Min-Raise Range
As we’ve said, against tight and predictable opponents, such as nitty multi-tabling SNG regs, you can often make exploitive min-raises with impunity. While you should also raise small with premium hands, such players will often let you continue to steal blinds relentlessly, not catching on that they can 3-bet wide and you’ll have to fold a large part of your range.
Against good thinking players, however, you must consider your overall strategy rather than look at individual hands in a vacuum. When playing against such opponents, your two options are simply to stick with a shove/fold game, or to add in enough strong hands to your raise/call range such that these players can’t exploit you through wide 3-betting. While shove/fold is an easier strategy to implement, a big benefit to raising smaller is that you’ll get to play more hands – i.e., you won’t be restricted to playing only hands that are profitable to open-shove.
The wider your opponent is 3-bet shoving, the more hands you should be raise/calling rather than raise/folding. For instance, suppose you’re on the button with a 10 BB effective stack, facing a tight-passive small blind and a very LAG big blind who 3-bets 50%. In this case, you should never raise/fold as you’ll win $150 at most half the time – as the SB will sometimes 3bet as well – and lose $200 over half the time. Any hand in roughly the top 25%, however, will be strong enough to raise small with the plan of calling the big blind’s shove.
If the big blind is an observant player though, he’ll see that you’re only raising with hands you intend to call and that are ahead of his range. He should respond by 3-betting tighter, at which point you may begin raise/calling less and raise/folding more. This process of adjustments will eventually reach an equilibrium if he is adjusting correctly.
Note also that just because you’re often raising small, that doesn’t mean you can never open-shove. With good semi-bluffing hands like low pairs, low aces, and mid suited connectors, you may still open-shove, electing to raise small with a polarized range of weaker hands you’re intending to fold, and stronger hands you’re intending to call.
One player category we haven’t yet addressed is the loose-passive player. Your strategy with a 10 BB stack facing loose-passive opponents should depend on how they respond to shoves versus small raises. A loose-passive player will call a min-raise with a lot of hands, but while some will also call shoves widely, many tighten significantly facing all-ins. So the decision of whether to open-shove versus raise small should be tailored to your specific opponents.
Antes and ICM
Let’s conclude by looking at the impact of antes and ICM on our analysis.
At a given stack depth measured in big blinds, antes should make you more inclined to open-shove rather than raise smaller. The reason behind this last statement is the pot odds you’ll be offered on a call when an opponent shoves. For instance, suppose the blinds are $4000-$8000-$1000, 9-handed, and the effective stack is 10 BB or $80,000. If you min-raise now and get shoved on by the big blind, the pot is $109k and it costs $60k to call. You’re getting much closer to 2:1 on a call, so while raise/folding is still a viable option against very tight and predictable opponents, you should be more inclined to open-shove to win the larger amount in the middle compared to the same stacks and blinds without an ante.
The ICM tax, meanwhile, has mixed effects on the open-shove versus raise small decision. Since chips decline in value, it is much more reasonable to decline good pot odds and fold after min-raising to preserve your stack. Good players, however, may exploit this fact and 3-bet very wide, forcing you to risk your most valuable chips or fold. Against such opponents, it is vital to have the first-in advantage so that you are the one forcing them to put their stacks at risk.
For instance, suppose it’s the bubble of a 9-man SNG with everyone having roughly equal 10 BB stacks. Against good, thinking players, they know that the ICM tax is so high that if you raise small, you will usually have to fold to a shove. However, while these opponents can profitably shove many hands over an open-raise, there are very few hands they can profitably call an open-shove with. So you should mainly open-shove or fold in this situation, unless you’re up against predictably tight opponents who will rarely widen their 3bet ranges.
Conclusion
While you should often shove or fold with an effective stack of 7-10 BB, there are many situations where you should raise small instead. It isn’t until you have a stack of approximately 6 BB or shallower where shove or fold are essentially your only two options. The best times to raise small with a short effective stack are exploitively against tight-passive opponents, or against loose-aggressive opponents when you’re balancing by raise/calling appropriately. Antes should make you more likely to open-shove at a given short effective stack depth, as should a high ICM tax when facing all but predictably tight opponents.
I would like to thank Team Moshman coaches MachtiSonni and Lallez0r, pioneers of short-stacked min-raising whose outside-the-box thinking inspired this article.
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