Blog Post • Friday, August 1, 2025

What Is Shopify Checkout Extensibility?

Blake WaldronBlake Waldron
Checkout extensibility | Checkout Components
Checkout extensibility

If you've ever tried to customize the Shopify checkout experience, you know the limitations of the past. Now, Shopify is ushering in a new era of flexibility with Checkout Extensibility - a modern, secure, and scalable way to customize your store’s checkout experience.

In this guide, we’ll break down what Shopify Checkout Extensibility is, how it compares to the legacy checkout.liquid method, what new tools it unlocks, and how you can start customizing checkout without touching a line of code.

What Is Shopify Checkout Extensibility?

Shopify Checkout Extensibility is the platform's latest framework for customizing the checkout and post-purchase experience. Unlike previous methods that relied on editing liquid templates directly, extensibility is built on a modular, upgrade-safe, app-based architecture.

This means:

  • You don’t need to touch Shopify’s core checkout code.
  • It’s built to scale with Shopify’s updates.
  • You can customize it with apps, extensions, and Shopify Functions.

It’s designed for Shopify Plus merchants, developers building apps for checkout, and now increasingly, non-technical teams looking for more control over the buyer journey.

Checkout Extensibility vs Checkout.liquid

Checkout Extensibility

checkout.liquid (Legacy)

Checkout Extensibility vs Checkout.liquid

Security

App-based, upgrade-safe

Direct code edits, prone to breakage

Performance

Optimized and scalable

Can introduce page load issues

Upgrades

Auto-updates supported

Manual updates needed

Custom UI

UI Extensions, Pixels, Functions

Liquid/JavaScript only

Access

Shopify Plus only

Shopify Plus only

What Can You Do with Checkout Extensibility?

Shopify Checkout Extensibility gives you powerful tools to transform the checkout experience:

🔧 Shopify Functions

Inject custom backend logic without middleware. Use it to:

  • Offer tiered discounts
  • Set advanced shipping logic
  • Create rule-based payment options

🧩 UI Extensions

Add custom components directly into predefined checkout surfaces, such as:

  • Product upsell cards
  • Gift messaging fields
  • Delivery date pickers

All with consistent styling that matches Shopify’s native UI.

📈 Pixels & Webhooks

Track events throughout the checkout funnel for:

  • Attribution
  • Conversion tracking
  • Custom analytics

Pixels run safely in isolated sandboxes, keeping performance high and data secure.

Real-World Use Cases

Here are some real ways brands are already using Checkout Extensibility:

  • Add gift note fields in the information step
  • Upsell related products based on what’s in the cart
  • Offer post-purchase add-ons with one-click checkout
  • Apply advanced discounts based on customer tags or cart value
  • Show delivery date selectors to set expectations pre-purchase

Whether you're trying to increase AOV, improve UX, or reduce support tickets—these customizations can have real business impact.

Want the Power Without the Code?

Customizing checkout used to require developer time, liquid knowledge, and ongoing maintenance. But not anymore.

Checkout Components is a no-code/low-code solution built on top of Shopify Checkout Extensibility. It lets you drag and drop elements into the checkout—like upsell cards, custom messages, or inputs—without writing a single line of code.

Built for marketers, ecommerce managers, and revenue teams, it lets you launch and iterate quickly, all within the bounds of Shopify's new checkout framework.