v3 API Blank Custom Fields using JSON Payload

0 Votes

When using the "Import Contacts using a JSON Payload" option, our Custom Fields are not being carried over to the Contact List. All other fields are being uploaded as expected (first name, last name, email, etc.), just not the Custom Fields. Both Custom Fields had already been created prior to using the JSON bulk upload. Below is an example of a current contact entry from the bulk upload:

        "first_name":  "Joe",
        "last_name":  "Smith",
        "email":  "jsmith@email.com",
        "cf:Location":  "Main Street",
        "cf:EmployeeType":  "Staff"

Is there something that I'm missing regarding the formatting of the Custom Fields in the JSON payload? Please let me know if there's any other information I could provide that would be helpful.

0 Votes

Hello AdamU27,


Thank you for reaching out to Constant Contact API Developer Support. My team is here to assist outside software developers with questions about building into Constant Contact's API.


If you reformat those to "cf:location" and "cf:employeetype" it should resolve the issue and populate the custom fields correctly for the contacts you are adding.


When you call GET /contact_custom_fields, you’ll notice it returns the value for the property "label” as the custom field appears in the UI, but the property for "name" returns a value that has removed any uppercase letters and replaced spaces with underscores.


GET custom_fields Collection



Please have a look and let us know if you have any other questions!


Courtney E.
Tier II API Support Engineer

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