Integrating a Klaviyo opt-in within a Zendesk form to collect GDPR-compliant consent is possible with a few steps. You can embed the Klaviyo opt-in directly into the Zendesk form by using custom fields or by embedding the Klaviyo form's HTML. This allows you to capture customer consent for marketing emails while they complete the Zendesk form for product testing requests.

Here’s how you can do it:

1. Embed Klaviyo Form HTML: You can manually embed the Klaviyo form's HTML into your Zendesk form. This ensures the form includes an explicit opt-in checkbox that complies with GDPR, allowing users to agree to receive marketing emails.

2. Use a Custom Checkbox: If you prefer to use Zendesk's native form elements, add a custom checkbox for email marketing consent. You can then use Klaviyo's API to sync this data with your Klaviyo account, adding subscribers to your mailing list.

3. GDPR Compliance: Ensure the opt-in checkbox is unchecked by default and clearly labeled, explaining what users are consenting to, which aligns with GDPR requirements. You may also need to adjust your privacy policy links accordingly.

For more details, check out Klaviyo’s documentation on GDPR-compliant forms and the Zendesk integration​