The Unique Identifier field is a custom field that the marketer creates. 

  • Specifically, it is a STRING data type.  We took this approach so as to provide the maximum flexibility in devising the formats for member ID, customer ID, etc. 
  • The Unique Identifier is a requirement to enable cross-channel messaging from within Journeys.
  • The “Send SMS” and “Send Push Message” Journey Action items ONLY become visible when the client defines a unique identifier for their account.


How to define the Unique Identifier:

  • The place to define the unique identifier for contact records is on the Account Settings page.  You’ll see a section on the bottom left hand side of the screen called “Unique Identifier”.
  • Click on the “CREATE” link and a modal will appear.  Note that it ONLY displays custom fields that are Strings.
  • Select the custom field, that you want to use as the unique identifier for your contact records.


Linking together email contact records, SMS contact records, and mobile app messaging contact records is currently done via List Import. 

  • Email List Import – The contact file must contain a column for the Unique Identifier (e.g.”member_id”, or “customer_id”, etc.) and a column for the email address
  • SMS List import – The contact file must contain a column for the Unique Identifier and a column for the mobile number
  • Mobile App List import – The contact file must contain a column for the Unique Identifier and a column for the mobile Device Token ID.


For more information on functionality and working of a Unique Identifier, please refer to the following link:

https://maropost.wordpress.com/other-information/unique-identifier/