This is not correct. Mailchimp does not require double opt-in. They used to recommend it strongly; now they just give you information about the differences [1].

This is not correct. Mailchimp does not require double opt-in. They used to recommend it strongly; now they just give you information about the differences [1]. Also, this only applies to a Mailchimp sign-up form. You can also add contacts manually, via import, or via the API; opt-in is assumed, even if you enable double opt-in. [1]: https://mailchimp.com/help/single-opt-in-vs-double-opt-in/ https://mailchimp.com/help/single-opt-in-vs-double-opt-in/