However, modern phones and mobile networks support message concatenation, which enables longer messages to be sent. We can help review your messaging and determine if an error was made, and put you in touch with our Compliance team if needed.A single SMS message technically supports up to 160 characters, or up to 70 if the message contains one or more Unicode characters (such as emoji or Chinese characters).

If you believe your messages are compliant with Twilio and carrier policies, please collect 3 or more examples of Message SIDs that have the “undelivered” status with error 30007, and then contact our Support team.

For actionable tips on reducing the risk of filtering, see How do I prevent my Twilio messages from being filtered (blocked)?.

Review the information in How Does Message Filtering Work? to understand what causes filtering and how to avoid it.

Ensure your messaging use case complies with Twilio's Messaging Policy and Acceptable Use Policy.Your message was flagged as objectionable and blocked by a wireless carrier.Your message was identified as spam or unwanted messaging by Twilio's message filtering system.Learn more about how message filtering works and how to avoid it: How Does Message Filtering Work?įor a detailed explanation of carrier filtering in the United States and Canada, please see SMS Carrier Filtering in the United States and Canada. These carrier filters are used to block abusive traffic, as well as to enforce rules or regulations about what types of messaging are allowed to that country or mobile network. Wireless carriers have filtering systems in place as well.

Twilio’s filtering system is in place to protect mobile subscribers from spam or other forms of malicious or unwanted messages.

This may be done by Twilio for violating Twilio’s Messaging Policy or Acceptable Use Policy, or by a wireless carrier for violating carrier rules or regulations.Įxamples of messaging that would be blocked by Twilio are spam, phishing, and fraud. If a message you sent is not delivered to the end device and returns a 30007 error code, this means that your message was filtered (blocked) by Twilio or by the carrier.

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