What is Double Opt-In?

Double Opt-In - also known as confirmed opt-in (COI) or verified opt-in - is a process by which an email subscriber has to confirm their subscription twice in order to be added to an email list. This involves the subscriber filling out a form and then confirming their subscription through a link or confirmation message sent to their email address.

The process of double opt-in helps ensure that the person subscribing really wants to receive emails from the sender, and that they have given explicit permission for their contact details to be used for this purpose. It is seen as best practice by many marketers, as it reduces the risk of spam complaints and can lead to higher engagement rates.

While double opt-in may result in fewer subscribers than single opt-in methods (where people are automatically subscribed after filling out a form), it can also lead to higher-quality leads and more engaged subscribers over time.