SMS error codes
This guide will help you to troubleshoot any SMS error statuses you may see. Each error code includes a description, possible causes and steps you can take to resolve the issue.
Status | Description | What to Do |
| Message is queued for delivery | No action needed. If delays persist, check network connection or contact support. |
| Message is scheduled for delivery | No action needed until scheduled time has passed. |
| Message sent to the network for delivery | No action required unless further updates don’t appear. |
| Message delivered to the handset | No action required. |
| Message is cancelled | Verify why message was cancelled. Attempt to resend or contact support if needed. |
| The message was canceled by ClickSend staff as its content did not comply with our guidelines. | If you believe your message was incorrectly flagged, or if you need clarification on the cancellation, contact ClickSend Support for further assistance. |
| Message is waiting manual approval from ClickSend staff | Allow time for approval. Contact support if status does not update. |
| Unknown failure | Retry sending. If problem persists, contact support for investigation. |
| Unknown subscriber; number is inactive or invalid | Confirm phone number is correct and active. |
| Unidentified subscriber; invalid number or network routing issue | Ensure recipient number is valid. Reach out to support if errors continue. |
| Illegal subscriber; rejection due to failed authentication or filtering | Verify recipient network compatibility with SMS. Contact support if needed. |
| Rejection due to subscription or network not supporting SMS | Verify that recipient’s network supports SMS services. Contact recipient for confirmation. |
| Absent subscriber; phone out of range or off for 12+ hours | Retry sending later. Error typically clears once recipient’s device is back online. |
| Memory capacity exceeded; recipient’s device lacks space for SMS | Contact recipient to free up space on device, then retry. |
| Rejected due to network congestion or error | Retry the message in a few minutes. Contact support if issue persists. |
| Rejected by the recipient network | Reach out to support. There may be network restrictions affecting delivery. |
| Temporary network error; ClickSend will retry automatically | Wait for retry. No action necessary unless error repeats. |
| Network timeout when delivering message | Retry the message. Contact support if persistent timeouts occur. |
| Network routing error | Verify recipient number and retry. Contact support if issue continues. |
| Anti-spam rejection by recipient network | Ensure message complies with anti-spam guidelines. Modify and retry. |
| Message delivery receipt expired | Retry message. If problem repeats, contact support for assistance. |
SMS sending speed and message throughput
ClickSend is built for speed. We start sending your messages to the network as soon as we receive them.
Most messages are delivered within 6 seconds.
We can accept messages at any rate—send them as fast as your system allows.
For high-volume sending (e.g. 100,000+ messages at once), we can configure a throughput of up to 30,000 messages per minute.
Need faster throughput?
If you're sending time-sensitive or mission-critical messages, let us know. We may be able to:
Increase the priority of your account
Configure higher throughput based on your use case
Several enterprise clients use ClickSend for urgent, large-scale communications. Reach out to support to see if you're eligible.