30004: Message blocked

Error 30004 indicates the destination number is blocked from receiving the message. You see an ErrorCode value of 30004 when a message transitions to a failed or undelivered state in the Programmable Messaging logs or status callbacks.

• The destination number is blocked from receiving messages, resulting in a Message blocked status.
• The recipient's device is turned off or out of coverage, which can cause the message to return 30004.
• The destination number cannot receive SMS (for example, a landline). For India, Do Not Disturb (DND) and domestic Distributed Ledger Technology (DLT) regulations can also block delivery.
• Carrier or compliance filtering blocked the content or sender, or Twilio applied internal filtering aligned with industry norms. These scenarios can result in repeated messages that fail with 30004.

• Reproduce and baseline the issue by sending a fresh test via the API. Check the recipient device for power and coverage, try a shorter single‑segment body, and test from a different Twilio sender instead of an Alphanumeric Sender ID.
• If the recipient previously opted out, ask them to opt back in by sending START or UNSTOP to your sender, and then retry. Attempts to message an unsubscribed recipient from your account fail with error 21610 until they opt back in.
• If filtering is suspected, adjust content to comply with Twilio's Messaging Policy and avoid prohibited or high‑risk content patterns.
• For delivery to India, make sure your approach follows the India SMS guidelines. International traffic may bypass DND, whereas domestic routes require DLT registration and are subject to DND. Select the appropriate route and confirm that the required registrations are complete.
• If the issue persists, collect recent Message SIDs that return 30004 and contact Twilio Support for further investigation.

• Debugging Tools
• Customize users' opt-in and opt-out experience with Advanced Opt-Out
• India: SMS Guidelines