Troubleshooting Carrier Blocking

Like email providers, mobile carriers use advanced filtering systems to protect their subscribers from unsolicited spam messages.  If you've found that many of your messages are not being delivered to your recipients, it's possible that your message, or your phone number as a whole, is being blocked by carriers. 

Here are a few questions that may help you identify and correct the issue:

  • Did the blocked message contain "spammy" content?
    • Are you sending messages in ALL CAPS?
    • Did you send a message that sounds like a business promotion? (Marketing and business promotions aren't allowed on local or toll-free numbers.)
  • Did the blocked message contain a link?
    • If you are using a public URL shortener like or, that could be causing your messages to be tagged as spam. Try using our built-in URL shortener instead, or include the full destination URL in your message.
    • If you notice that messages that containing your MojoTxt short domain (i.e. are being blocked, please contact us and we'll switch you to a new domain.
  • Did you send messages to people who didn't specifically opt-in?
    • If so, they may have reported your messages to their carrier as spam.  Carriers take these reports very seriously and will block your number if they receive an excessive amount of reports. 
  • Are you sending an MMS to a large number of recipients?
    • Carriers filter MMS messages very strictly.  Unless you are sending from a toll-free number, we recommend sending MMS to groups of less than 100 for the best deliverability.
  • Are you sending a too many messages over a local phone number? 
    • If you are sending more than a few hundred messages per day, we recommend switching to a toll-free number to send to larger groups. Carriers expect local numbers to be used by individuals, while toll-free numbers are cleared for high-volume messaging.

If none of the above suggestions correct the issue, it's possible that your phone number has been blocked from sending messages at the carrier level.  In this case, we have a couple of options available to help:

  1. If you are using a toll-free number, we can request that the carrier unblock your number. Just open a support ticket and we'll assist you. 
  2. If you're using a local number, we may be able to request that your number be unblocked, however, the best option to prevent carrier blocking is typically switching to a toll-free number, which are carrier-approved for high volume message sending. 

Still having trouble?

If these tips don't solve the problem, please reach out and we'll be happy to assist!