If you have AT&T, forward the text to 7726. You will get a response to reply with the spammer's number. I just reported this text to AT&T using this method.
If I get a spam text message, what should I do?
•Forward the spam message to the short code 7726 (SPAM) so that AT&T can start an investigation.
•Do NOT respond directly to a phone number where you believe the spam text originated. Responding will alert the spammer that your number is genuine.
•iPhone: Tap Edit. Tap to select the message, and then tap Forward. Enter 7726 in the To field of the message to forward. Tap Send.
•Android: Press the message (being careful not to activate a link), choose Forward (from the menu), and forward to 7726.
•Blackberry: Open the message, then using the Menu key, select Forward (from the menu), and forward to 7726.
•Windows: Press the message (being careful not to activate a link), choose Forward (from the menu), and forward to 7726.