A double opt-in occurs when a user signs up for an email marketing list, and then an email is sent out to the user which includes a link to click and confirm the subscription. Only after the confirmation click is completed will the user officially be added to the email marketing list. Double opt-in can also be referred to as confirmed opt-in.

The double opt-in method has a few more steps, but it's still easy to use. It's just like single opt-in, but it includes a confirmation step where the contact receives an email and has to confirm their signup. An advantage of the double opt-in process is that you'll know the email address is for a valid, monitored inbox. We recommend double opt-in for companies who aren't focused on audience growth, or who have had low open rates or abuse complaints in the past. Companies may also decide to use a double opt-in process to satisfy regulations that may apply in the particular market or country in which they operate.

Double opt-in is an email subscription method. It means that users are added to your mailing list only after they confirm the subscription two times. With this method, you’ll get high-quality leads and better email deliverability.