Double opt-in is an email verification method intended to confirm the email address of people who submit forms.
With double opt-in enabled, an automated verification email is sent to all new contacts created as the result of form submissions.
Enabling double opt-in?
You can enable double opt-in on the Account settings page in the Forms section.
Consent and subscriptions
Double opt-in is to confirm email addresses. It does not indicate consent or subscription preferences. A contact can have express consent but if their email is still unverified you can’t send emails to them.
You can't send emails to contacts who came for a form submission and haven't verified their email when double opt in was enabled. These contacts are marked as contacts with "unverified email" in your account.
Contacts with unverified emails don’t count towards the active contact count used for billing.
Form submissions only
Double opt-in only applies to contacts who enter your database via form submissions. Contacts added manually, via import or integrations don’t have a double opt-in option.
Pros and cons or double opt-in
There are several benefits of enabling double opt-in:
Contributes to a clean email database since every new contact who submits a form is required to confirm their email address before you can send them messages
Reduced bounce and complaint rates in email campaigns.
Ensures that someone can’t subscribe on behalf of other people using their email address in forms.
The downside of double opt-in is that you will almost certainly lose ‘real’ subscribers who fail to confirm their email during the verification process.
You can view all unverified emails from the database overview page.
Contact details page
On the contact details page you can see the verification status, which can be:
Yes: the contact verified their email via double opt-in. Can receive emails.
No: the contact didn't verify their email via double opt-in. Cannot receive emails.
N/A: double opt-in wasn't a requirement when this contact submitted a form. Can receive emails.
Re-send verification email
You can re-send the verification email to contacts. Click the "Re-send verification email" link from the contact details page. (verification emails cannot be re-sent in bulk)