Note: This feature is optional and is NOT turned on by default.
It's important to know that when double opt-in is enabled, any "unconfirmed contacts" will be dropped from future emails. Unconfirmed contacts include new contacts who fill out forms and do not click through in the double-opt in email, as well as existing contacts who have never been sent an email from your HubSpot account prior to enabling this feature.
Contacts who have previously been sent emails from your HubSpot account count as "confirmed contacts" and, therefore, do not need to go through this double opt-in process to receive emails after enabling this feature. Furthermore, if the double opt-in feature is disabled at any point, any contact that was created during the time it was enabled will become eligible for email.
When you import a list, you need to specify that you are importing an opted-in list.
It's also important to note that this feature will only work if your account has COS Landing Pages.
Navigate to Email
From your HubSpot Dashboard, navigate to Content > Email.
Manage Email Settings
Once in the Email tool, go to the Manage tab. On the left-hand side, click on the link to Manage Settings.
Email Settings > Double Opt In
Once in your Email settings, click on Double Opt In in the left-hand side menu.
Double Opt In email
Once at the section for the Double Opt In email feature, before we can enable this feature we need to click Create/Edit Email below Request Email.
Customize and personalize your email
Now that you're in the email tool, you can add content to your double opt-in email to personalize it for your contacts. Once you've edited your email to your heart's content, choose Publish Opt In Email.
Choose Confirmation Page
Now that you've created your Request Email, you'll want to choose your Confirmation Page. You can choose one that already exists from the dropdown or click to Create new page. Now you should be able to Save changes.
You'll also have the option of deciding whether or not someone receives a follow-up email after they confirm their subscription. To do this, check the box next to Include follow-up email, Create/Edit Email if you haven't already (repeat steps 5 & 6 above), then you'll be able to Save Changes once more.
At this point, you can decide whether you want this feature enabled (at all), enabled for all pages, or enabled for some pages only. Click the radio button next to your choice and click Save changes.
Send opt-in email to individual contact
Once you have the double opt-in feature enabled, you can also manually send an opt-in email to a contact by going into the individual contact record, clicking the gear next to their name (at the top-left), and choosing Send opt-in email.
Please note: manually sending an opt-in email will not work for unsubscribed contacts, as it would be a violation of CAN-SPAM laws.