Possible answers: --If it allows you to block a number when you have it selected, you do not have to worry. It will not block an unknown number from your phone.; --All calls you make outside of sms will go to at&t. Click " contacts ", then click " block number ".; --If the number you dislike is from " private number " or " anonymous " you should ask the person or telemarketer to remove you from their phone or list and never call you in the future. It is a good idea to enroll your number in the us " do not call " registry no matter what wireless service you use.; --The address Sign into your account on att's website. If you do not have an att account yet, click the link on your home page to connect to your account.;Choose from options above and answer: What most naturally follows?

How to block a number on att
Write down the number that you would like to block.
Make sure you have all 10 digits available before you arrange to block it.
At&t does not have the capability to block anonymous numbers from your phone.
Answer:
If the number you dislike is from " private number " or " anonymous " you should ask the person or telemarketer to remove you from their phone or list and never call you in the future. It is a good idea to enroll your number in the us " do not call " registry no matter what wireless service you use.