As long as you store the chicken in an airtight container or a strong freezer bag with the air squeezed out, it will last for up to four days in the fridge. If you want to keep it for longer, you will have to freeze it. It is best to freeze it as soon as you have cooked and cooled it down. If you keep it in the fridge for a couple of days it will lose taste and texture and it is also an open invitation for bacteria to develop.