Pass a hidden KickoffLabs form field to Mailchimp

Last reviewed: 2026-09-23

A KickoffLabs form can include a hidden field. In the KickoffLabs editor, add that field with the key and value you want attached to each lead, then preview the form state and publish. Check the captured value on a new lead under Leads first.

In KickoffLabs, open Leads → Lead delivery → Mailchimp. Connect the target audience and enable Send captured custom fields. Create a compatible optional audience field if required by Mailchimp. Submit a new synthetic lead and inspect the Mailchimp contact. The current KickoffLabs form uses automatic prefixed custom-field delivery; the classic Manage Merge Fields → Add Field mapping screen is absent. A required Mailchimp field with no value can reject a contact. If the hidden field is missing or uses a different key, contact support with the field key and test lead before changing the audience for all subscribers.

For destination fields and mapping, follow Mailchimp audience fields overview. Confirm a test contact contains the expected data.

Need help? Email support@kickofflabs.com with the campaign URL, integration, and result of a synthetic test. Keep API keys private.