Mailchimp Master List Best Practices
MailChimp recommends you have a single master list. Having a single list makes it much easier to manage subscribers and reduces costs. We have made easy to use a master list by adding the ability to push additional information from the system to merge tags in MailChimp.
To create a Master List for use in Mailchimp, go to the Contact Search and find all contacts you would ever want in Mailchimp based on search criteria. Then save your search and give it a name. We recommend ‘MailChimp Master’. If you want every contact on your list, you can search with no filters selected.
Go to Marketing > Contact Lists and create a new list.
Add your saved search filter to this list. Now all the contacts who match (or will ever match your search) will get added to your master list automatically. All of the contacts in the search results will show up on the list; the list updates every 15 minutes.
You can regularly push your list to Mailchimp to keeps contacts up to date. If any contacts unsubscribe, they will stay on the list but won’t receive emails.