Folding the small blind is okay

No contribution you've already made to the pot should keep you in the pot. This is common advice, yet in one situation many people seem not to be able to follow it. In the small blind many people tend to call even though it isn't worthwhile.

Pot Odds

The small blind simply alters pot odds.

The small blind is not a magical position which overwhelmingly forces a player into the game. Rather it alters the pot odds for the player so they will be compelled to play a slightly larger range of hands. A player holding Q♦ 9♣ might normally not play, but in the small blind with 3 callers they may decide otherwise.

Pot odds calculations pre-flop however are entirely distinct from pot-odds after the flop. It isn't 100% clear exactly what the winning chance of a pocket is before the flop. Therefore knowing the pot odds isn't necessarily the key to your decision.

So assume a table of pre-flop odds is available. And there are in fact numerous tables showing different odds. Simply calculate the pot odds and compare.

A given pocket has 7:1 odds. In order to get equal or better odds for a call in the small blind 3 or more callers would be required, including the big blind. This gives 3.5BB:0.5BB, or 7:1 odds.

Chart Based

Given the disagreements about what exactly the winning chance of a hand is pre-flop, it isn't easy to rely on pot odds to make a choice in the small blind. Most players tend to refer to a table, written or instinct based, as to when they should play.

If the table being consulted is one of the mammoths with every position and holding available then it has probably already made the decision for you. If it is just a general guide as to what are good and bad hands, some thought is required.

In a class based table one might be willing to call a lower class hand than normal in the big blind. Such calls are implicitly based on pot odds: stepping one class down is the acknowledgement that the odds have slightly improved.

This must however be countered with the poor positions of the player. Once the flop comes they are now forced to act first. Unless they hit their unlikely flop their options are quite limited. So for the most part calls in the small blind are quite often to be followed with an initial bet, or a fold.

Mikey holds 5♠ 6♠ in the SB. He's got a book which indicates this is a folding hand unless 4 players call before him. It mentions nothing of the small blind, so he assumes that 2 callers will be enough. There are two limpers, so he limps in as well. The flop comes A♦ K♥ 7♠. Given the 3 other limpers he assumes an aggressive bluff won't work, so he checks. The button raises and Mikey folds his hand.

A Big Blind Raise

Many callers prime the big blind.

Another critical factor leaning against the small blind is the action to be taken by the big blind. If the big blind has a marginal hand they may simply check and hope for the best. This is exactly what a small blind caller would hope for.

Should the big blind have a playable hand, they will not likely enjoy having many callers around. And since many small blind calls will require many other callers, this situation is quite common. To reduce the competition the big blind may raise.

The raise must be large as well, otherwise it won't work. For example, if there are 5 callers, the pot is now 5xBB big. A raise of 2xBB still offers 7:2 odds for the first caller. And should they call, that goes up to 9:2 for the next caller. The small blind then gets 13:2 pot odds, which isn't much worse than the 9:1 they had when they first called.

Jim is holding a marginal hand in the small blind. His table says he needs 4 callers in order for him to also call. However Raoul in the big blind is crazy and usually raises in that position. Jim gets his 4 callers but mucks his hand anyways. Sure enough, Raoul raises to 6xBB.