Yes, you can differentiate people who reached checkout by checking if they entered their payment information and set up separate email flows for them in Klaviyo. Here's how you can do it:

1. Track Payment Information: Ensure that your integration with Klaviyo tracks whether a customer has entered their payment information during checkout. This can be done using custom fields or order properties. Set up API-Based transactional events

2. Create a Segment: Create a segment in Klaviyo that includes customers who have entered their payment information. You can use conditions like order properties contains "payment_info_entered" to filter these customers. Unlock Deeper Customer Insights with Shopify's Checkout Blocks and Klaviyo Integration | Klaviyo Community

3. Set Up Separate Flows: Create two separate email flows - one for customers who entered their payment information and another for those who didn't. Use the segment you created to trigger the appropriate flow based on whether the customer entered their payment information.

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