What happens if I delete data in either platform?
When a customer, order, product, variant, or abandoned checkout is deleted in Shopify, we will delete the corresponding data in Mailchimp as well. Note that for customers, we will only delete the e-commerce customer data in Mailchimp and not the contact on your Mailchimp audience. You will need to manually delete the Mailchimp contact from your audience if that is desired.
When a contact is deleted in Mailchimp, we will not modify any data in Shopify.