When is data sent from Impact Stack to Mailchimp?

1. Subscription: Contact has subscribed to one of the Mailchimp lists by opt-in in Impact Stack
2. Contact update: There has been an update to a contact that already has a subscription to any audience [1] in Mailchimp. Most contact updates are triggered by the submissions (regardless of whether the subscription has an opt-in or there is no change to opt-in status).

What data is sent from Impact Stack to Mailchimp?

1. Native tags: This includes the URL 'tags' parameter value, the action node ID and the action tags defined in Impact Stack's 'Autosegmentation Tags'. Tags are added to the existing list.
2. Audience merge fields: All data mapped by relevant audience merge fields in Mailchimp. The mapping can be adjusted in Mailchimp by adding desired audience merge fields. For a full list of available audience merge fields, please see here. These values will be overwritten in the contact across all Mailchimp audiences each time the contact is updated. Data that is not available in Impact Stack but is available in Mailchimp will not be overwritten.
3. Unsubscribes: in case of opt-out contact will be unsubscribed in Mailchimp.

What this behaviour looks like in specific cases

Contact already exists in Mailchimp

When is data sent from Impact Stack to Mailchimp?

There has been an update to a contact that already has a subscription to any audience [1] in Mailchimp. Most contact updates are triggered by the submissions (regardless of whether the subscription has an opt-in or there is no change to opt-in status).

What data is sent from Impact Stack to Mailchimp?

Tags will be added to the native tags list. All other data mapped by relevant Mailchimp tags will be overwritten for the contact in Mailchimp across all Mailchimp lists.

Contact is new in Mailchimp

When is data sent from Impact Stack to Mailchimp?

Contact has subscribed to one of the Mailchimp lists by opt-in in Impact Stack

What data is sent from Impact Stack to Mailchimp?

All submission data, including tags and data that is mapped with relevant Mailchimp audience merge tags.

[1] By default, contact data is updated across all audiences in Mailchimp. If you want contacts to receive updates from Impact Stack only in some audiences, there is an option to define the specific audiences.