How to add Submarine Flow Properties to Klaviyo Templates

Overview Prerequisites Step 1: Verify Data is Coming Through Step 2: Create the Flow in Klaviyo Step 3: Create/Select Your Email Template Step 4: Add Event Properties to Your Template Step 5: Find Property Names in Shopify Flow Step 7: Testing Your Flow Adding a Filter for Testing Running a Test

Overview

This guide walks you through how to add event properties from Submarine's Shopify Flow into your Klaviyo email templates for subscription notifications.

Prerequisites

Submarine integration set up in Shopify

Klaviyo account connected to Shopify

Flow already configured to send subscription events to Klaviyo

Note: to get the Event properties to show you will have to have had the event fire into Klaviyo once or twice.

Step 1: Verify Data is Coming Through

Before building your email template, confirm that Submarine is sending data to Klaviyo:

In Klaviyo, navigate to Analytics > Metrics

Filter by Shopify Integrations using the dropdown

Scroll to find the Upcoming Subscription Order metric

Click on a recent activity and select the three dots → Activity Details

Verify you can see data like:

Next delivery date

Total price

Currency

Product information

If no data is showing then there is an error with the Flow. Please reach out to Submarine support for help.

Step 2: Create the Flow in Klaviyo

Important: You need to create the flow first before the email template can access the event properties.

Go to Flows in Klaviyo

Create a new flow with the trigger set to your subscription event (e.g., "Upcoming Subscription Order")

Add an Email action to the flow

Save the flow as a Draft (this prevents it from sending while you're testing)

Step 3: Create/Select Your Email Template

In the flow you just created, select or create your email template

This connection allows the template to access the event properties from the metric

Step 4: Add Event Properties to Your Template

Click into a text block in your email template

Highlight some text or position your cursor in the area you want the data to be.

Look for Personalization in the top toolbar (next to the emoji icon)

Filter properties to Event

In the drop down click View all event properties

Click and copy the full property path (it will look like {{ event.property_name }})

Paste this directly into your email template where you want the data to appear

Some data will need to be filtered and displayed correctly, for example we send dates in ISO format so to get these to look nice you will have to add extra data to the property path. Example for Upcoming Billing at, this would be: {{ event.subscriptionUpcomingOrderExpectedBillingAt|datetime_from_string }} this will show as : Jan. 21, 2026, 2:12 p.m.

For any help with filtering data please reach out or review Klaviyos documents here

Step 5: Find Property Names in Shopify Flow

If you need to know what properties are available:

Go to Shopify > Flow

Open the Submarine flow template

Click on the Track Event action

Review the Event Property labels - these are the exact property names you'll use in Klaviyo

Common properties include:

subscriptionExpectedDelivery - Next delivery date

subscriptionTotalPrice - Order total

subscriptionStatus - Customer subscription status

Note: Property labels are consistent across emails, so subscriptionStatus will be the same in all your templates!

Step 7: Testing Your Flow

Adding a Filter for Testing

Before going live, add a filter to prevent sending to all customers:

In your Shopify or Klaviyo flow, add a Conditional Split or Filter

Set it to only trigger for your own email address

This allows you to test without emailing customers

Running a Test

Ensure the flow is set to Live (required for testing)

Go to Recent Runs in the Flow

Select from the last Flow Run

Click the three dots and select Retry Run

Check your inbox for the test email

Verify all properties are displaying correctly