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.

Our native Klaviyo integration is available with a Pro or higher subscription.
All subscription plans can add custom forms using the Form Embed block.

Before you start, as a best practice we recommend you also connect your campaigns to Monster Leads as a backup.

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. Before you start, you’ll need a Klaviyo API Key. You can generate and copy an API Key from your Klaviyo account following this guide.
  2. Navigate to the Integrations view in the campaign builder, search for and select Klaviyo.
    Search for and select Klaviyo as the integration you would like to add to OptinMonster.
  3. Enter a Klaviyo Account Name (*internal use only) and your Klaviyo API Key in the appropriate fields, then select the Connect to Klaviyo button.
    Name your Klaviyo integration and add the Klaviyo API Key.
    *The Klaviyo Account Name can be anything that helps you identify the specific integration within OptinMonster. It’s possible to add more than one Klaviyo integration to your account and this is an easy way to differentiate between them when assigning integrations to individual campaigns.
  4. Required: Once the Klaviyo integration has been connected select the Klaviyo List you wish to send leads to from the Provider Lists field.
    Select the Klaviyo List to add leads to from your OptinMonster campaign.
  5. When you’re finished, Save your campaign.

Add Extra Fields

Field Mapping

New: Our Klaviyo integration supports Field Mapping, so you can easily add radio buttons, phone fields, text areas, number fields, lists, and more!

Get started using Field Mapping with Klaviyo.

Before you begin using Field Mapping with Klaviyo, please consider the following:

  • Custom fields are referred to as Custom Properties in your Klaviyo account.
  • Custom fields must be manually created in your Klaviyo account before they can be mapped to in OptinMonster.
  • The following custom fields are reserved in Klaviyo and cannot be mapped to:
  • Custom field names should only contain letters, numbers, and underscores.
  • You can manage your custom fields in Klaviyo following this guide.

Form Embed Block

Alternatively, you can add any Klaviyo webform to your campaign using our Form Embed block.

Get started adding a custom form to your campaign.

Email Automations

To send emails automatically to new leads you’ll want to configure email automations within your Klaviyo account.

The following guides from Klaviyo may be helpful to get started:


We strongly recommend you test the optin form before publishing your campaign to ensure it is working as you expect.

Before you begin, please be aware of the following details when testing Klaviyo integrations:

  • Previously submitted or already subscribed leads may be treated differently by Klaviyo than new leads. For this reason, we recommend using a completely unique email address each time you test submit your campaign’s form. You can use a free tool like or learn how to create unlimited unique email addresses from a single Gmail account.
  • If the lead is captured in Klaviyo but you do not receive any automated emails it indicates the integration from OptinMonster to Klaviyo is correct, and the issue is with the automated email configuration. Klaviyo controls email automation exclusively. If you require assistance in troubleshooting email automations we recommend reaching out to Klaviyo support directly.

Get started testing with the Live Site Inspector tool.

Spin-a-Wheel Support

If you are configuring a Gamified spin-to-win campaign, spin-a-wheel support is automatically enabled when using our native Klaviyo integration. The Coupon Label and Coupon Code will be passed as custom fields with each lead.

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Can I send leads to more than one Campaign?

Yes! See our Lead Sharing guide to accomplish this.

How do I configure single or double opt-in?

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

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

Yes! You can add a phone field. Learn how to capture phone numbers with OptinMonster.

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

The referral URL is automatically passed to Klaviyo in a custom property called referrer.


The campaign is capturing leads but shows 0 conversions in analytics.

Confirm that conversion tracking is turned on for the submit button in your campaign. See our guide on How to Enable Conversion Tracking.