New and inexperienced players might understandably consider calling to be a simple part of the game in that it’s a less urgent and therefore less interesting alternative to raising. However, this would be a serious underestimation, and the so-called Flat call is a perfect example as to why.
When a player is said to have flat called – also known as ‘flatting’ or ‘smooth calling’ – it means in most cases that they have elected ‘just’ to call when they would have been quite justified in raising instead. The point of describing this specific type of call as smooth calling and so on is to emphasise the fact that a raise would generally be expected in that situation, so only calling could be considered as an atypical move.
A common example of flat calling is when a player flops a strong hand but, instead of responding to a bet by raising – as many would do with a powerful hand – chooses to slowplay with just a call. The idea is usually to invite an opponent to continue being aggressive with a view to allowing them to commit further before hitting them with a big raise.
An advantage of flat calling is knowing you’re strong, yet your opponent remains in the dark or cannot easily evaluate the situation. A call on the Flop or Turn, for example, could be interpreted as signaling a weak hand or, in contrast, a sign of strength.
Those players who are particularly tight might flat call without necessarily having a grand plan that means suddenly piling on the pressure on the next street, rather they are the kind of player who does not want to take risks even with a good hand, but are happy to keep calling against hands they believe to be weaker than their own.