This question is all dependent on your cell phone. Fido itself can either block all or none, but a lot of phones will have some form of "blacklist" feature. Usually it's found in your recent callers list, by viewing the options. If you're unsure, a quick Google search with your phone's model number, brand, and the word "block" will usually get you the information you're seeking.
Likewise, most smartphones have apps available that can block specific numbers and even unknown callers.
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I am a Fido employee, but my comments are my own and do not necessarily represent the views of Fido or its affiliates. Je suis un(e) employé(e) de Fido mais mes commentaires sont les miens et ne reflètent pas nécessairement le point de vue.
