Typically avocados last a couple days in the refrigerator so you should put them in as soon as possible in order to avoid having to throw them away because they go bad. Those who do not plan on eating or using the avocados they bring home form the store within the next couple of days should think about putting them in the freezer until they are going to use them.
They will last as long as you need them to in the freezer. Just make sure that you put your avocado in a vacuum-sealed container so that no air gets in. This way you will be able to ensure that they do not go bad at all. Spoiled or unripened avocado can sometimes cause problems with upset stomach, vomiting, and diarrhea which you will want to avoid altogether.