Message Error Codes Overview
Message errors show you why specific messages didn’t reach their recipients. These codes are generated by our message provider and appear in your Message Export report for both account and campaign exports. By understanding these codes, admins can see which messages failed, how those failures affect billing, and where to focus further deliverability review.
This guide explains what message errors are, how to locate them in your exports, and what each error code means so you can interpret your reports with confidence.
TABLE OF CONTENTS
- Where to Find Message Errors
- Billable vs. Unbillable Errors
- Billable Message Errors
- Unbillable Message Errors
- Using Message Errors to Review Deliverability
- Unlisted Errors
- Download a CSV of All Error Codes
Where to Find Message Errors
Message errors appear in your Message Export, which you can download as an account or campaign export. You can review details about every column in this export in the guide ThruText Export Types. Each row in your export will include the following error-related columns:
- error_code: A numeric code generated by our message provider.
- error_type: A brief description of what the error code means.
- billable: Indicates whether the message counts toward billing (Y = Yes, N = No).
Billable vs. Unbillable Errors
Some message errors are billable, and others are not. Billable messages are included in your account usage metrics. You can check whether an errored message is billable by reviewing the billable column in your export. Unbillable errors do not count toward message totals in Usage Analytics. You can use these error types to reconcile your billed usage with your exports and to understand which failed messages still incurred a cost.
Billable Message Errors
These errors occur after your message leaves GetThru and is processed by the carrier. The message may still be billable even if it doesn’t reach the recipient. Below is a list of common billable error codes and their meanings. For each error code, review the description and further description to understand what happened with the message and how it may affect your deliverability review.
These billable errors are listed from most common to least.
| Code | Description | Further Description |
|---|---|---|
| 9902 | Timed out waiting for delivery receipt. The reason a delivery receipt was not received is not known. | Our message provider timed out waiting for the delivery receipt from the carrier; this could be because the downstream provider did not send the requested delivery receipt, or they sent it after the system timed out at two hours. |
| 4720 | Carrier Rejected as Invalid Destination Address | This could mean the number is just invalid or is not enabled for messaging. We recommend not texting this number again. |
| 4700 | Carrier Rejected as Invalid Service Type | This usually means messaging (SMS or MMS) is not supported by the carrier or handset. We recommend not texting this number again. |
| 4750 | Carrier Rejected Message | The destination carrier has rejected the message but provided no specific reason. For AT&T traffic, this could mean Spam. |
| 4770 | Carrier Rejected as SPAM | The carrier is reporting this message as blocked for spam. Spam blocks could result from content, SHAFT violations, or the sending phone number has been flagged for repeated spam content. |
| 4470 | Rejected as SPAM | This message has been filtered and blocked for spam. Messages can be blocked for various reasons, including, but not limited to, volumetric filtering, content blocking, or SHAFT violation. |
| 5620 | Carrier Application Error | The carrier is reporting a general error associated with their application processing the message. |
| 9999 | Unknown error from downstream. Carrier reported a failure code that is unknown | Provider does not recognize the vendor's error response or does not have the vendor code mapped internally. |
| 4702 | Destination subscriber is unavailable. | This error indicates the subscriber is unavailable. There are several reasons for this; the subscriber has turned off handset, the destination is unreachable or barred, SIM card is full, voicemail is full, or cannot reach the destination handset. |
| 4751 | Message is too long or message length is invalid for the carrier. | Carrier has rejected for message length being invalid or too long. For messages to AT&T users, messages with 10 segments or greater will be rejected. If using MMS, we recommend keeping attachments under 750KB. |
| 4781 | AT&T rejected due to 10DLC volumetric violation or throttling | AT&T rejected due to volumetric violation. This error can indicate throttling by AT&T for 10DLC or other reasons, including high spam rates. |
| 4740 | Carrier Rejected as Invalid Source Address | Carrier is rejecting the message due to invalid source address - the number does not exist in the numbering plan. Other reasons for this error code is the source carrier is invalid or disabled or source not authorized or the number type is not supported. |
| 4701 | Destination is not reachable and SMS service is not available. | Carrier service is reporting the destination is not reachable or the SMS service is not available. |
| 4752 | Message is malformed for the carrier. | Carrier is rejecting the message malformed; this could be because of a blank message, unacceptable data value, or the receiving device does not accept messages with more than 160 characters. |
| 4780 | T-Mobile rejected due to volumetric violation | Your T-Mobile EIN Daily Cap limits how many segments you can send to T-Mobile customers in a given day. |
| 4771 | Rejected due to shortened url | There was an error with the shortened URL used. Our message provider blocks messages that use Bit.ly or other generic URL shorteners. If you are using a URL shortener, we strongly recommend using GetThru shortened trackable links because they are unique to each account. Since all messages are subject to blocking, no particular URL(s) is guaranteed to make it through the carrier filters. As long as you follow the best practices and avoid disallowed URL shorteners, you should be able to maximize deliverability. |
| 30005 | Unknown destination handset | The destination number you are trying to reach is unknown and may no longer exist, the device you are trying to reach is not on or does not have sufficient signal, the device cannot receive SMS (for example, the phone number belongs to a landline), or there is an issue with the mobile carrier. |
| 30003 | Unreachable destination handset | The destination handset you are trying to reach is switched off or otherwise unavailable. |
| 30008 | Unknown error | This means that your message was not delivered for unknown reasons. Our carrier partner provided a very generic error message that provides no further details. |
Unbillable Message Errors
These errors occur before the message is sent or when the number is invalid in a way that prevents billing. You are not charged for these messages.
These unbillable errors are listed from most common to least.
| Code | Description | Further Description |
|---|---|---|
| 4360 | Message expired | Message was not sent because the specified expiration date passed before the message was able to send. |
| 4406 | Unallocated to number | The To number associated with this message, while a valid North American number, is not yet assigned to a carrier and the message cannot be sent downstream. |
| 4476 | The source TN is not registered to a 10DLC campaign. | The source TN is not registered to a 10DLC campaign. |
| 4410 | Could not download media | There was an error retrieving the media. |
| 5106 | Impossible to route / Attempt to deliver through retries has failed. | Impossible to route / Attempt to deliver through retries has failed. |
| 21610 | Attempt to send to unsubscribed recipient | Opt these contacts out. One of our providers has a system to opt-out contacts automatically when they send specific keywords. Attempting to reply to these conversations will error. |
| 21408 | Permission to send an SMS has not been enabled for the region indicated by the 'To' number | You have attempted to send an SMS or MMS to a country that is not supported. |
Using Message Errors to Review Deliverability
Message errors are one of several tools you can use to review how well your messages are being delivered. When you see a pattern of errors in your exports, it’s helpful to consider:
- The volume of each error code compared to total messages sent
- Whether errors are related to contact data, message content, or number configuration
- The potential impact of sending additional outreach to contacts who previously encountered errors
We recommend using these codes alongside your campaign analytics and overall message review process to decide whether any follow-up action is appropriate for your program. For examples of how to interpret delivery data and plan next steps, see our guide on How to Assess Message Deliverability.
Unlisted Errors
If you encounter an error code that is not listed in this guide or the attached CSV, please contact support. We can help you confirm what the error means and whether it may be affecting your deliverability.
Download a CSV of All Error Codes
You can download a full CSV of all billable and unbillable error codes from this guide. Use this file if you want to filter, sort, or match codes directly against your message exports in a spreadsheet or BI tool.