How It Works

Understand what happens behind the scenes when a Post Purchase Upsell offer is triggered. Learn how the extension behaves within Shopify Checkout, and how Nosto processes and delivers the offer.

How the Post Purchase Flow Works

When a customer completes a checkout in Shopify, the Post Purchase Extension is triggered immediately after the payment step. Here’s what happens step by step:

1. Order is created Shopify creates the order and marks it with status On hold. This status prevents the order from moving to fulfillment while the post-purchase extension is active.

2. Nosto is called Shopify loads the Nosto Post Purchase Extension. Nosto uses the order information and customer context to run your campaign logic.

3. Offer page is rendered — If a matching offer is returned (based on product availability, filters, segment, etc.), the offer page is shown directly inside the Shopify Checkout. — If no products are matching or if anything goes wrong, this step is skipped automatically.

4. Customer interacts

   • If the offer is accepted:

     • The product is added to the order

     • The customer is charged using the same payment method

     • Shopify updates the order and removes the On hold status.

   • If the offer is declined or if the timer runs out:

     • The customer continues to the Thank You page

     • Shopify also removes the On hold status.

5. No interaction / customer leaves the page

   • Shopify waits up to 1 hour

   • Afterwards, the order is automatically resumed

   • Order status is updated accordingly

What’s Handled by Nosto vs Shopify

Offer logic & personalization	Nosto
Segmentation logic	Nosto
Discount application	Nosto
Payment processing	Shopify
Order editing (add item)	Shopify
Order status management	Shopify

Timeouts & Edge Cases

• The offer page is only active once per checkout and during timer duration – customers cannot return to it later.

• Shopify auto-resumes the order after 60 minutes if the customer closes the page.

• If Nosto doesn’t return any valid products, the post-purchase step is skipped entirely.