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      SMS/MMS Restrictions

      The following behaviors can lead to a toll-free number being temporarily blocked:

      • Identical content with changing domain URLs
      • Short URLs (bit.ly, owl.ly, etc.)
      • Redirect URLs
      • Rotating toll-free sender caller IDs

      Sprint and T-Mobile are heavily blocking toll-free numbers. T-Mobile classifies all toll-free traffic as business-related or Application-to-Person (A2P). As a result, delivery rates may be lower on T-Mobile compared to other networks.

      AT&T and T-Mobile no longer accept SMS or MMS campaign submissions that include any charitable donation element. Texts directing recipients to a website for credit card or other donation methods will not be approved. However, text-to-donate campaigns will continue to be allowed on AT&T and T-Mobile.