Hey there, @Lu86! Thanks for contacting us. Our system does not notify the person you've blocked. However, their text will not go through when texting your specific number. This leads them to think that you've blocked them, but we don't text them or notify them that you blocked him/her.
We don't send anything to them, @Lu86. They only suppose that you've block them since they're unable to text you. Boost Mobile doesn't notify them in any way about it.
Hello, @Lu86. Thank you for stopping by. We're more than happy to assist you. We don't send a notification or text message to the person that has been blocked. -Kira_M.