How to Customize Email Templates in Klaviyo
When you use Klaviyo as your email provider in STOQ, you customize email templates in Klaviyo using Klaviyo's built-in email editor. STOQ sends product details, customer data, and links to Klaviyo each time a notification fires. You insert these as dynamic variables in your template to create personalized emails.
Overview
STOQ triggers metrics in Klaviyo when a product comes back in stock or a customer places a preorder. Each metric carries event data you can reference in your Klaviyo email template. You control the layout, styling, subject line, and content entirely in Klaviyo's editor.
Prerequisites
- A paid STOQ plan.
- A Klaviyo account with access to flows and email templates.
- Klaviyo connected in STOQ. Go to Back in stock > Notifications > Customize > Email > Send emails through and select Klaviyo.
- A Klaviyo flow created and verified in STOQ.
Open Your Flow Template
- Log in to Klaviyo and go to Flows.
- Open the flow triggered by the relevant STOQ metric (e.g., Back in stock alert (STOQ) or Preorder confirmed (STOQ)).
- Click the Email action, then click Edit Email to open the template designer.

Customize the Subject Line
- Click the Subject field at the top of the email editor.
- Insert dynamic variables using the format
{{ event.variable_name }}. - Enter Preview text below the subject line.
Example subject lines:
{{event.product_title}}is back in stock!`Your preorder for {{event.product_title}} is confirmed

Design the Email Body
Use Klaviyo's drag-and-drop editor to build your email. Insert STOQ variables to display dynamic content.
- Product image: Add an Image block and set the source to
{{event.image_url}}. - Product details: Add a Text block with variables like
{{ event.product.title }},{{ event.product.price }}, and{{ event.product.variant_title }}. - CTA button: Add a Button block and set the URL to
{{event.checkout_link}}(direct checkout) or{{event.product_page_link}}(product page). - Unsubscribe link: Add a text link at the bottom with the URL set to
{{event.unsubscribe_link}}.

Available Variables
Test Your Template
- In STOQ, go to Back in stock > Notifications > Customize > Email > Klaviyo settings.
- Click Send test event to trigger a test event in Klaviyo.
- In Klaviyo, open the email editor and click Preview & Test to see the template rendered with real data.
- Send a test email to yourself to verify the final result.

Known Limitations
- All template design happens in Klaviyo. STOQ's built-in email editor does not apply when Klaviyo is selected.
- Product titles are sent in your store's default language. Handle translations in Klaviyo if needed.
- Back in stock and preorder flows use different variables. Make sure you use the correct set for your flow type.
- Paid STOQ plan required.
Troubleshooting
Symptom | Likely Cause | Fix |
|---|---|---|
Variables show as blank | Incorrect variable path | Use |
Product image missing | Product has no image in Shopify | Upload an image to the product in Shopify |
Checkout link not working | Variable not inserted correctly | Use |
Email not triggered | Flow is in Draft mode | Set the flow to Live in Klaviyo |
Test event not appearing | Klaviyo app not connected | Verify connection in Back in stock > Notifications > Customize > Email > Klaviyo |
FAQs
Q: Where do I find the list of available variables in STOQ?
A: In the Klaviyo email settings section within STOQ, click the available template variables link under the flow setup instructions. Go to Back in stock > Notifications > Customize > Email > Klaviyo.
Q: Can I use the same template for back in stock and reminder emails?
A: The alerts and reminders use separate flows triggered by different metrics. However, the event data structure is the same, so you can duplicate your template design across both flows.
Q: Can I use conditional logic in my template?
A: Yes. Klaviyo supports template language. For example, use {% if event.notification.is_reminder %} to show different content for reminder emails, or {% if event.customer.locale == "fr" %} for language-based content.
Q: How do I loop through multiple products in a preorder email?
A: Use Klaviyo's template language: {% for product in event.products %}{{ product.title }}{% endfor %}. This lets you list each product in the preorder.
Q: Do I need to update my template when STOQ adds new variables?
A: No. New variables are added to the event payload automatically. Your existing template continues to work. You can optionally update it to use new variables.
Updated on: 29/04/2026
Thank you!