How to Enter a Blacklist on SMS

1. Use your cellular service provider's SMS blocking options. Some providers allow you to set different blocking options at the customer service website. AT&T, for example, offers a 'Messaging Preferences' page, where you can block all SMS sent over email, SMS sent from specific email accounts or domains or all SMS. After choosing one of these options, AT&T will SMS a one-time code to the cellphone for authentication. Enter that code on the 'Messaging Preferences' webpage to have the selections take effect.
2. Install SMS-blocking software on your cellular phone. This is a more flexible alternative. For example, an app called 'iBlackList' allows iPhone users to filter SMS by a variety of criteria, either black- or white-listing them source by source. 'iBlackList' can be configured to ignore SMS from individual phone numbers or email addresses. You can protect your configuration with a password for additional security.
3. Write SMS-blocking software for the cellular phone, if the phone can run code that you develop. This is the most complex and most flexible alternative. The criteria that such an application can follow to black- or white-list an SMS are endless--they are limited only by your programming skill. For example, SMS could be blacklisted depending on how many previous SMS have been received from the same source, or depending on how many of them have actually been read by the user. The SMS-Popup Application webpage (see References) includes sample code for a telephone running the Android operating system.