Stealing pre-flop is an art and a science at the same time. On one hand, you need to be able to carefully select the spots where stealing is likely to be profitable, but on the other hand you will need to know how to execute. Some players will blindly make attempts to steal pre-flop without any real reason or strategy in mind. As is the case with most poker plays, any move that is without reason and motivation is going to end up failing more often than it succeeds. The truth is that stealing pots pre-flop is actually quite simple and systematic, and that many players end up making it way more difficult than it needs to be.
There are three different spots where you are going to be stealing pre-flop: from late position, in the small blind, and in the big blind. There is little to no reason why you should be gunning for blind steals when you are in early or middle position. The reason for this is that you will end up getting way too many calls and re raises to ever make this move profitable. The very reason that steals work is because raises do not have to fight their way through that many players. When you start raising from early or middle position, however, you are now being forced to get folds from the majority of the table. If you are raising from EP or MP, you should have a hand that is strong.
The first thing that you need to understand about stealing pots pre-flop is what types of hands are going to carry the highest success rates. Since you are stealing and do not desire to actually see the flop, you would think that your hands are largely irrelevant. While this may be the case, you can't discount all of the times where you are going to get calls and will have no choice but to play your hand post-flop. When you do get calls, your opponent will frequently be putting you on a reasonable hand. They might give you credit for a pair, two broadway cards, or something else along those lines. As a result, a deceptive range of stealing hands will go a very long way towards winning big pots when you really were only hoping to take down the blinds.
The most ideal hands for steals pre-flop are big suited cards like K3, Q4, etc. These types of hands play well in these situations because they either flop hard or miss hard. You will hit some big flush draws, random trips, and even two pair on occasion. Since your opponent is unlikely to put you on K3 suited, a flop like K3x is going to look harmless to their QK or AK, for example. The beauty in these hands is that you can fire a c-bet if you miss and promptly give up if you face further resistance. Or, you will have an easy time laying down K3 when you miss and your opponent leads out. These hands are exactly what you should be looking for when stealing pots pre-flop.
Types of Players to Steal Against
One thing that will remain universal when stealing pre-flop is that you need to target the right types of opponents. If you are gunning for players who never fold, you are just asking to fail. If you raise way too much against players who are super tight, you are going to waste a lot of money. Even if you are playing otherwise tight players and have a super loose image, you are going to get called more often that you would like.
Whenever you make a steal attempt from any position, first make sure that the other players are capable of folding. This should all go without saying, but one of the main reasons why players fail at steal attempts is because they were trying to procure folds from players who never had the intention of folding, regardless of the action in the hand, your image, or anything else.
Stealing from Late Position
Late position is the best time to steal the blinds. You will have no money already invested in the pot, have position on your opponents, and there is always a chance that you actually have a strong hand. With that said, it is also the most obvious time for a steal in the eyes of your opponents. Regardless, this doesn't mean that you shouldn't be shooting for the dead money in the blinds whenever you can.
Bet sizing for late position steals is going to be different than what you will implement in the blinds. If you are one off the button, a good raise size is 3x the big blind. This assumes, though, that your standard raise is to 4x. By raising to 3x instead, you are still using aggression and will put your opponent to a decision, but you are not putting a lot of your money at risk. When you shift to the button, you can now trim that raise size down even further to 2.5x.
Depending on the game, your opponents, etc., sometimes you will want to adjust these raises to 3.5x and 3x accordingly. Also remember that these figures apply almost exclusively to online play. In live games you will need to make normal sized raises, but stealing pre-flop in live poker is not usually advisable at all simply because so many players hate folding any hands regardless of strength or position.
Stealing from the Small Blind
The small blind is an interesting spot for steals because you are fighting for two blinds, but one of them is your own money. Once you post the blind, however, that money becomes worth fighting for. You will get a lot of folds from the small blind, but you should be wary of the times where you get called or are raised. The small blind is forced to play every pot out of position, so you should be intent on winning pre-flop. If you feel like there is a good chance that you will get called, mucking is the better play. It is important to remember that the value in a small blind steal increases when there is a late position limper. This is some added money that you can now win and it is unlikely that the limper is all that strong.
If you are making steal attempts from the small blind, you have to be prepared to make post-flop bets. Don't steal in the small blind, get called, and then check fold. This is exactly what your opponents (should) want and it will unnecessarily cause you to bleed money from your stack. Give up pre-flop or continue with your aggression post-flop, but don't fall somewhere in between.
Stealing from the Big Blind
The big blind will not only enable you to make open raises when attempting to steal pre-flop, but it will also give you opportunities to re-steal. In late position, most steal attempts will be open raises, and the case tends to be the same in the small blind as well. In the big blind, however, you will be able to re-raise those late position and small blind raises as a re-steal.
If you are re-stealing from a late position player, you will need to be armed with a lot more aggression than if you are aiming for the small blind. The reason for this is that the late position player will have position on you and it is possible that they actually have a strong hand. If the small blind opens, they are very likely to be weak and will also need to play out of position post-flop.
If the pot limps to you with only the small blind in the hand, you should be raising with an extremely wide range of hands. You do not need to even have exceptionally playable hands in these spots because you have so many other advantages going for you. Some players even argue that you should raise the big blind against a small blind limp every single time regardless of hand strength.
Stealing from the big blind will get an awful lot of folds, but you also have to get ready to fire out many continuation bets. The aggression should slow down drastically at this point, however. Don't go crazy trying to double and triple barrel in pots where your original intent was to simply steal the blinds. Being sucked into a small pot where you have a weak hand is one easy way to hand over money to your tighter opponents.