I get far more annoyed with text message spam than I do with email spam. My iPhone dings every time I receive a text message, and I check it as soon as I can. I really, really resent the intrusion when it’s spam. And of course there’s the cost. I don’t pay per text message, but lots of people do. I do, however, have a monthly limit and don’t want spammers using it up. I searched every nook and cranny on the iPhone to find a way to block the spam, to no avail. Turns out AT&T actually does provide a way for you to block text messages. They just don’t publicize it much. Put your iPhone down right now and go to http://mymessages.wireless.att.com/. You’ll need to register here, even if you already have an AT&T login for your regular account. Once you’re there, you’ll have a few different options for blocking text messages.
You can block all SMS messages and multimedia messages sent to you as email. This is how most spammers get you — they send their junk to MobileNumber@txt.att.net or MobileNumber@mms.att.net. I recommend you block both of them.
AT&T does give you an option to set up an alias address, so if there are people you know who send you SMS messages via email, you can give them the alias and still foil the spammers.