This page lists error response codes for webhooks in Marketo.

1000 and 1001 are generated by Marketo, and 2xx to 5xx are errors returned from the system that the Marketo webhook is calling.

In order for Marketo to map values back into a field, the webhook response code must be of the 2xx variety. If the intent of the webhook is to change values in the Marketo lead record via the response, then the Web Service which is called must return 2xx, all other response codes will result in the webhook being ignored for the purpose of updating lead record values.

Response Code



This indicates that the ‘Call Webhook’ flow action is being housed within a Batch Campaign. Webhooks can only be fired from trigger campaigns.


This indicates that the web service emitted an empty response body.

Catching a Webhook Error

Errors from Webhooks can be caught and handled by the Webhook is Called trigger:


Response – Response is the literal response payload which was received by the request.
Error Type – This corresponds to the Reason-Phrase of the HTTP status message.

These can be used to handle and react to predictable errors and exceptions.  Depending upon what service you are integrating with, it may be possible to recover certain classes of errors automatically, while alerts can be created to notify users of unexpected errors.