Integrating OptiMonk Campaigns with Klaviyo

This article will walk you through integrating Klaviyo with your OptiMonk campaigns. Once you have completed the steps outlined in this guide, your subscribers will automatically be transferred to your Klaviyo mailing list when they fill out an OptiMonk popup form. This may come in handy if you run marketing campaigns on a regular basis, so subscribers who signed up via OptiMonk will also get notifications about your upcoming promotions and news.

In this article:  


Set up the integration in the OptiMonk campaign settings

To set up the integration between OptiMonk and Klaviyo, please follow these steps:

1. First, please log in to your OptiMonk account at

2. Select Campaigns on the left menu, then select the Campaign you wish to connect with Klaviyo:


3. Click on Edit settings on the right-hand side:



4. Click on Add new integration under Add integration:



5. Select Klaviyo from the list of available integrations:


6. You will see the following window:



7. You will need to insert the API key from your Klaviyo account. To find your API key, please log in to your Klaviyo account in a new browser window, and click on your username in the top right corner and choose Account to continue:



8. If you haven’t created your own API key yet, click on the Settings tab and select API Keys:


9. Click on the Create API Key button. This will generate an API key that you can insert to your OptiMonk account:


10. Now, copy your key, under Private API Key column and paste it into the respective field in your OptiMonk account:


Give the integration a name, then click Done to continue.

11. In the last step, you will be able to select the list from your Klaviyo account where new subscribers will be forwarded from your OptiMonk Campaign:



12. Input Field Bindings

Here you can find all data from your OptiMonk campaign that you can transfer to your Klaviyo form. For every input field on your OptiMonk campaign, you can assign a field in your Klaviyo list. Once you have linked the corresponding fields, the data from your OptiMonk campaign will be transferred to your Klaviyo list.


When you set up the connection between the fields, please note that for the default Klaviyo fields you have to use unique field identifiers preceded by a $ sign. However, you can also add any custom field identifiers without the $ as well.

The default field identifiers in Klaviyo are as follows:



The visitor's unique identifier


Email address


First name


Last name


Phone number


Your position within the company


Organization name












Ticking the Checkbox


Static Fields

You can create static fields as well. Static fields can be used basically to add additional and fix information to your campaigns and subscribers’ data, in this regard it is just like a note or a tag. To add a static field to your campaign, you have to add a specific (static) value in the ‘Field values’ column and select the Klaviyo field to which you would like to assign it. Once it is done, this value will be sent to the Klaviyo field every time someone subscribes.


2) Examples

Let’s see how to associate the fields with some practical examples as well:


1) OptiMonk campaign collecting basic subscriber data, such as first name and email address:

Sample popup with email and first name input elements:

Input field bindings: with these settings, only the first name and the email of your visitors that you’ve collected on the popup form will be transferred to your Klaviyo list:

After subscribing, you will see your leads' data in OptiMonk as:

The contact information in the Klaviyo list will contain the following data:

2) OptiMonk campaign collecting basic subscriber data with coupon code

Sample popup with a first name input field element, an email input field element, and a coupon code element:

Input field bindings: By applying these settings, the first name, the email address, and the displayed coupon code will be transferred to your Klaviyo list:

After subscribing, you will see your leads' data in OptiMonk as:

The contact information in the Klaviyo list will contain the following data:

This ‘OptiMonk campaign coupon code’ (which you can name as you wish) data will automatically appear at your Email templates - custom properties in Klaviyo. If you insert this property into your form you will be able to set up your email flow using the coupon codes displayed to your OptiMonk subscribers.

3) OptiMonk campaign with basic subscriber data, custom fields, and a static field

Sample popup with email and custom fields, plus a static field:


Input field bindings: In this case, the email address, the custom field data (Favorite color), and also a static field (OptiMonk Summer Campaign) will be transferred to the Klaviyo list:


After subscribing, you will see your leads' data in OptiMonk as:

The contact information in the Klaviyo list will contain the following data:

13. Once you are done with the field binding, click Done and Next in the top right corner to finish the setup.

That's it! :) Whenever a visitor signs up through your OptiMonk popup, they will automatically be added to the Klaviyo list you have selected.


Double Opt-in


I also would like to announce that the double-opt-in is now a switchable option in Klaviyo integration.

A subscriber will only be validated and added to your Klaviyo subscriber list in case they accept the follow-up confirmation email.

If the double opt-in option is not something that is legally necessary for your country, you can turn off the option as far as we know. Klaviyo offers a guide for this option, which you can access at the following link:


If you have any further questions or need any help, please contact us at, and we will be happy to assist you :)


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