Does "Blocking" numbers use up voicemail space?

Blocking numbers has nothing to do with voice mail. You can block as many numbers as you like. However, if people who are blocked leave you voice mail, those messages will be filed in your deleted voice mail folder.

Yes.

That's because true blocking must be done before the call connects to the phone. What blocking on the phone does is ignore blocked numbers, it doesn't actually block them. The only way to prevent this is to arrange with your carrier to block the numbers at their switch, before they get to your phone. Most carriers offer this service. Most also charge a monthly fee to enable it.

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