Carrier Violations

Owned by Former user (Deleted)
Last updated: Dec 17, 2019
2 min read

  • Background:

    • Marketers have over time realized that SMS is a cheap and more reliable method of reaching prospective customers. Similar to email, they have begun to spam us as consumers with junk. Because of this, carriers have begun to implement filtering to block these unwanted messages and just like email, sometimes valid messages get caught by this filter. The key difference between this and email is that you can still look at your spam messages but carrier filtering blocks these messages even before they get to the user’s phone so there is no way for the user to recover them. This is communicated to W2H via a 30007 error code via Twilio.

    • So, if a message is not delivered to a participant’s cell phone in W2H because of a 30007 error code, this means that the message was filtered out by the participant’s carrier and the patient / participant has not received this message.

    • We are seeing most of these issues with specific carriers - Sprint, T-Mobile and other smaller carriers using Sprint’s network (such as Boost Mobile).

  • What should you do?

    • Carriers do not publish the algorithms they use to block SMS. So you should know that sending messages via SMS does not guarantee delivery. Some recommendations to consider when designing your study’s text message language:

      • Identify your study or program in the message

      •  Avoid:

        • Overly long messages

        • Overly capitalized messages

        • $ signs

        • Hyperbole

        • Using aggressive language that can make users suspicious of a message

      • Provide opt-out instructions on how they can unsubscribe

      • If administering surveys, sending them as a long link instead of a short link (talk to your W2H liaison to implement this) or try to use SMS based surveys where possible

      • Create an incident so you get notified whenever this happens.

  • What are we doing about it?

    • We’re exploring buying a shortcode. This is a worthwhile investment for us and we were ready to make this happen until Twilio communicated to us that carriers like Sprint and T-Mobile are still likely to block these. Since these are the two carriers that we face almost all our problems with, we’re trying to figure out an alternative plan. We might stil invest in a shortcode since our volumes continue to increase. We will keep you posted.