How to Connect OptinMonster with Klaviyo

OptinMonster offers seamless integration with Klaviyo email marketing service. Connecting OptinMonster to your Klaviyo email list is very easy.

In this article, you’ll learn how to connect Klaviyo with OptinMonster.

Before You Start

Here are some things to know before you begin:

Connect Klaviyo

When you create a campaign in OptinMonster that you intend to collect leads with you’ll want to integrate with one or more services to send those leads to.

To send leads to Klaviyo, follow these steps:

  1. Navigate to the Integrations tab in the campaign builder.
  2. Click Add New Integration.
    Monster Leads Add New Integration
  3. Search for and select Klaviyo from the dropdown field.
    Klaviyo Integration
  4. Log into your Klaviyo account to obtain your API Key. To do this:
    1. In your Klaviyo account navigate to the Account page from the dropdown menu next to your avatar and name.
      Click Account
    2. Next, select the API Keys link under the Settings drop-down menu.
      Click API Keys
    3. If you haven’t already created a specific API Key you wish to use, select the Create API Key button.
      Click Create API Keys
    4. When creating a new API Key give it a proper label as well so you can easily identify where you’re using the API Key in the future. Select the pencil icon under the Label column:
      Add Label to API Key
    5. A popup will appear for you to enter the API Key label. When you’re finished, select the Save API Key button.
      Click Save API Key
    6. Copy the specific API Key you’ve created and want to use.
  5. Returning to the OptinMonster campaign builder, paste your API Key into the corresponding field.
    Don’t forget to add a unique label for easy identification (internal use only).
    Connect to Klaviyo
  6. Next, select the Connect to Klaviyo button.
  7. Once connected, select the email list you want to add new subscribers to.
    Klaviyo Email Lists
  8. When you’re finished, click Save.


How do I configure single or double opt-in?

See our guide on single vs. double opt-in for Klaviyo.

Is it possible for me to add a phone field to my campaign?

Yes! You can add a phone field. Check out how to capture phone numbers with OptinMonster here.

How can I send the referral URL with the lead so I know on what page the visitor signed up?

This happens automatically. In Klaviyo, this will be in a custom property called referrer.