While setting up an integration with your email marketing software, some providers let you turn on double opt-in from inside OptiMonk. This article explains what it is, why it is worth using, and where to find the setting.
What is double opt-in?
If this option is on, a visitor who subscribes through your popup first receives an automated email in which they have to confirm manually that they want to subscribe. Until they confirm, they will not receive emails from you.
Why is it important to use double opt-in?
You get a better quality mailing list, because every email address on it has been confirmed twice. Without double opt-in you risk keeping bad addresses on your list: users make spelling mistakes, and sometimes competitors fill the form with non-existent addresses that damage your sender reputation.
With a double opt-in subscription you can also start the conversation right away, because you are sending a confirmation email anyway. In it you can tell subscribers more about your brand, ask them to add your address to their address book, or give them a special offer.
One more advantage: statistics show the unsubscribe rate is 7% lower than with a single opt-in subscription.
What happens if you do not use double opt-in?
If the option is off, your subscribers are added to your email list automatically as soon as they sign up.
Where do you switch it on?
Double opt-in belongs to the provider, not to the popup, so OptiMonk only shows it for the providers that accept it per campaign. You find it while adding the integration: Campaigns → open the campaign → Integrations tab → Add integration. Providers with extra choices get a Settings step between Account and Field mapping — that is where these controls live.
CleverReach V2
The Settings step asks for three things:
| Field | What it does |
|---|---|
| Group | The CleverReach group new subscribers are added to. |
| Opt-in mode | Leave it empty for single opt-in, or choose Double opt-in (send confirmation email — requires a form). |
| Double opt-in form | The CleverReach form the confirmation email is sent from. Only used when the opt-in mode above is set — pick the group first, because the form list depends on it. |
Maileon
| Field | What it does |
|---|---|
| Opt-in permission | The permission level recorded with the subscriber: None, Single opt-in, Confirmed opt-in, Double opt-in, Double opt-in plus, Other. The default is None. |
| Send double opt-in email | A switch that forces the double opt-in confirmation email. |
Mailigen
| Field | What it does |
|---|---|
| List | The Mailigen list new subscribers are added to. |
| Double opt-in | A switch: require a confirmation email. |
| Update existing contacts | A switch: update an already-subscribed contact instead of only creating new ones. |
Everyone else: set it on the provider's side
For every other provider — Klaviyo, Mailchimp, Brevo (Sendinblue), HubSpot and the rest — there is no double opt-in switch in the OptiMonk wizard. Whether a new subscriber has to confirm is decided by the list's own opt-in setting in that tool:
Mailchimp: the OptiMonk wizard asks for the list and, optionally, the interest groups — not for double opt-in. Set it on the Mailchimp audience.
Klaviyo: set it on the Klaviyo list (Klaviyo's guide to the double opt-in process).
Brevo (Sendinblue): your subscription form is the OptiMonk popup, so use Brevo's marketing automation to send the confirmation email (Brevo's guide).