You may want to look to your right under More LIke This and view similar threads. I believe if a blocked caller calls you, they get a message along the lines of 'your call can't go through'. Texts may depend on the carrier and/or phone ... I've read some posts that say that the text appears to be sent successfully, it just never reaches the recipient. On my phone, if I text a Verizon customer that I know has texts blocked, my phone says it can't send the text message.
When you block a number, blocked individuals who call you will hear the message:
Welcome to Verizon Wireless. The number you were trying to reach has calling restrictions which has prevented the completion of your call.
A blocked individual may see a text message failure notification on their end when they send you a message.
You will not receive a notification that a blocked number attempted to contact you.
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