SMS Delivery Report Error Codes

Delivery reports track the status of SMS messages from Airship’s third-party providers to your audience and may contain an error_code to describe why your message was not delivered.

Airship’s standard error codes for the most common errors encountered:

Error codeDescription
0Unknown error
10Landline or unreachable carrier
16Message blocked
61Message filtered
64Error, blocked due to exceeded quota
150Unknown destination handset
152Numeric Sender ID Not Provisioned on Carrier
300Unreachable destination handset

Some codes aren’t necessarily errors and indicate that a message has not yet been delivered, most notably 400 (queued) and 401 (dispatched).

The following example shows one of many error_code values relevant to SMS delivery report events:

Example SMS Delivery Report
  "body": {
    "interaction_type": "delivery_report",
    "name": "dispatched",
    "properties": {
      "error_code": "401",
      "sender": 18587323362,
      "vendor": "CLX",
      "vendorDeliveryId": "ZLOiTjmZfV6r0-Eo"
    "source": "API",
    "triggering_push": {
      "push_id": "7764f7bd-a206-4219-9933-a9bcb7dc9979"
  "device": {
    "channel": "73c29b53-a00a-4567-9ccd-1d726013699d",
    "delivery_address": "19712754475",
    "device_type": "SMS",
    "identifiers": {
      "sender": "18587323362"
  "id": "0f7d521f-dc6c-4530-9623-91fb8d370db5",
  "occurred": "2020-06-01T18:26:12.575Z",
  "offset": "1000032182771",
  "processed": "2020-06-01T18:26:13.558Z",
  "type": "CUSTOM"

In addition to these common errors, other errors might be returned, depending on your delivery service provider, Sinch or Twilio. Review the following sections relevant to your service provider to determine the meanings of error codes.

Sinch (CLX) Error Codes

Sinch was formerly known as CLX. For all error_code values that apply when a delivery report’s vendor property is CLX, see Message Error Specification in Sinch’s HTTP Basic for SMS documentation.

Sinch (CLX) MMS Result/Error Codes

The following error_code and report_code values are most common and relevant for MMS messages when a delivery report’s vendor property is CLX:

Error or report codeDescription
N101Message Sent
N102Message Sent/Delivered
E101Message Failed
E102Message Sent/Expired, Sent/Rejected, Sent/Failed or, Sent/Not Supported

For all Sinch MMS error codes, see in Sinch’s XML Service Appendix.

Twilio Error Codes

For error_code values that apply when a delivery report’s vendor property is TWILIO, see Twilio’s Error and Warning Dictionary.