Now you can block yourself from receiving unwanted text messages that are sent to your phone. It's free and easy. Just send a text message to 9999. In your message, type "Block" (space) and then the number you want to block getting text messages from (ex. Block 9995551234). Then simply send the message. You will get a text message that confirms the number has been blocked from your text messages. You will not be charged for sending this message or for the confirmation message.
If you block a number and later change your mind, you can unblock it by texting to 9999 and typing "Allow" (space) and then the number you want to unblock. You will receive a text message that confirms the number is unblocked. You will also not be charged for these messages.