Unsubscribes and billed contacts
Mailchimp webhooks
When you choose the audience of a language, the module registers a webhook in Mailchimp: an address of your shop that Mailchimp calls for every change made on its side. There is nothing to configure in Mailchimp.
- subscribe: a contact subscribes from Mailchimp, the matching PrestaShop customer becomes subscribed;
- unsubscribe: a contact unsubscribes, through the link of an email for example, the customer becomes not subscribed;
- cleaned: Mailchimp discards an invalid address, the customer becomes not subscribed.
The webhook address carries a key specific to your installation, checked on every call. The shop must be publicly reachable, over HTTPS.
Catching up missed unsubscribes
A shop in maintenance mode, a firewall or a network outage is enough for notifications to be missed, and Mailchimp does not replay a lost webhook: PrestaShop then keeps unsubscribed contacts as subscribers. The Apply Mailchimp unsubscribes button, in the List tab, closes this gap:
- first run: the whole audience is processed, which catches up the backlog accumulated since the module went live;
- subsequent runs: only the changes since the last run are read;
- one-way: the alignment only writes to PrestaShop and sends nothing back to Mailchimp.
A contact unsubscribed in Mailchimp cannot be resubscribed through the API: only the recipients can do so themselves, from a form. The module therefore never resubscribes anyone.
Stop paying for non-subscribed contacts
Mailchimp bills unsubscribed contacts and those who never subscribed, even though it sends them no campaigns. With the Only subscribers option of the Exclusion tab, the Archive the N contacts not subscribed button of the List tab archives them in Mailchimp:
- archived contacts no longer count in your plan, remain in your Mailchimp account and can be restored at any time;
- contacts unsubscribed in Mailchimp also become unsubscribed in PrestaShop;
- a contact that PrestaShop knows as a newsletter subscriber is never archived.