Shopify Checkout Extensibility Explained - A Complete Guide


Christine Hannivan


Temps de lecture

5 mins
Shopify Checkout Extensiblity

While the decision to implement it is still a bit contested in the ecommerce community, the deadline for Shopify’s deprecation of checkout.liquid is quickly approaching, and Shopify Plus merchants need to be ready for the final plug to be pulled on their current checkout page set up in August of 2024.

In this article, we’ll dig into checkout extensibility, Shopify’s replacement for the checkout.liquid file, explain what’s changing and the reasoning behind it, and break down how ecommerce agencies can help with the transition to this new customization environment. 

What is Checkout Extensibility in Shopify?

Checkout extensibility is Shopify’s newest approach to allowing users to modify and customize their ecommerce store’s checkout experience for their customers. Before checkout extensibility, merchants used checkout.liquid, a highly flexible file that Shopify Plus stores could edit to control the look and feel of their checkout process. 

Checkout extensibility does away with the checkout.liquid approach in favor of new extensibility widgets, functions, and branding APIs that enable stores to customize their checkouts without worrying about spending hours on checkout.liquid development time and missing out on Shopify updates that aren’t compatible with their checkout.liquid file.   

What is happening to checkout.liquid?

Shopify has begun phasing out the use of the checkout.liquid file. With checkout extensibility, all apps become extensions of the checkout page. Starting August 2024, checkout extensibility will completely replace Shopify scripts and checkout.liquid.

Here is the full timeline for the implementation of checkout extensibility and phase-out of checkout.liquid for Shopify Plus merchants:

  • Feb 13, 2023: checkout.liquid was deprecated for information, shipping, and payment pages
  • Nov 7, 2023: checkout.liquid apps with script tags and additional scripts were deprecated on the “thank you” and “order status” pages.
  • August 13, 2024: Customizations for the information, shipping, and payment pages of checkout will be turned off
  • August 28, 2025: Checkout.liquid customizations for the “thank you” and “order status” pages that have been achieved using checkout.liquid and apps using script tags and additional scripts will continue to work alongside checkout extensibility until this date.

The shift from checkout.liquid to checkout extensibility is driven by a significant issue with the former. Merchants using checkout.liquid are essentially locked into a specific version of checkout once they set it up. This poses a constant threat that updates to Shopify might disrupt what merchants have painstakingly developed in their .liquid file. 

This not only limits Shopify’s ability to make meaningful changes to checkout but also puts merchants at risk of their customizations becoming incompatible with exciting platform improvements. 

What are the Benefits of Checkout Extensibility? 

Every time Shopify makes a change, users of checkout.liquid need to test their functionality against these changes to ensure that nothing will break if they update. This creates more work for developers and a reluctance to adopt Shopify features like Shop Pay, which has been shown to convert up to 50% more than guest checkouts, for example. 

If merchants stay on one version of Shopify checkout for too long, there can also be other repercussions, such as a lack of alignment with constantly changing policies, such as accessibility laws (WCAG), GDPR, or Payment Card Industry (PCI) compliance.  

Shopify’s goal with checkout extensibility is to relieve merchants and Shopify developers of the burden of dealing with the aforementioned issues so that customizing the checkout experience is easier and more flexible for everyone. 

Shopify Plus checkout extensibility also creates a bit of a competitive landscape between app and widget creators where developers are competing against each other to create the best tools to better ecommerce metrics like conversion rate optimization (CRO), customer lifetime value (CLV) or return on ad spend (ROAS). As we all know, competition fuels innovation, and with the upgrade to checkout extensibility, we expect to see many exciting checkout customizations moving forward. 

Simply put, checkout extensibility is a more secure and upgrade-safe option for Shopify Plus merchants than checkout.liquid.

What An Ecommerce Agency Can Build with Checkout Extensibility

Whether you’re just starting out with Shopify and are looking for the best ways to customize your checkout with this new checkout editor, or you’ve been around for years and need help upgrading from checkout.liquid to extensibility, an ecommerce agency like Blue Badger can help get your online store sorted. 

Here are a few ways you can leverage an ecommerce agency to help with the deprecation of checkout.liquid.

1 - A Checkout.liquid Audit

Whether you haven’t started on the upgrade to checkout extensibility yet (the clock is ticking!) or you’ve already transitioned but need a fresh set of eyes to review your fixes to ensure that you’ve maintained your store’s liquid functionality, an agency can audit your setup and propose/implement an upgrade plan. 

With the upgrade deadline quickly approaching, now is the time to make sure everything you have done to transition over is enough and that everything is working as it should before you’re completely cut off from checkout.liquid for good, and having an agency available to help you out here is invaluable.  

2 - Add Checkout UI Extensions to Your Checkout Page.

An agency can set you up with custom Checkout UI Extensions to place above and below all of your store’s checkout elements to unlock tons of functionality. Checkout UI Extensions are essentially building blocks that can be placed throughout your checkout to customize it to your store and offerings. 

These blocks can display additional items in the checkout based on what products are already in the customer’s cart, collect additional information–like a gift message or special instructions—at certain points in the checkout, or place banners to communicate important information to customers. Ecommerce agencies can recommend extensions to match your checkout.liquid setup, or they can even build something new and custom for you. 

3 - Update Branding

Even though Shopify-powered checkouts will always have that Shopify look, there is a lot to be done in terms of brand-related customization to the checkout that an agency can take on to create a cohesive experience that is in line with the rest of your store’s look and feel. 

An agency can help you with a rebrand and/or implement it, from updating logos and text/background colors to changing wallpaper and customizing accent buttons. 

4 - Customize your Backend with Functions

Shopify Functions allow developers to customize their store’s checkout experience further by modifying the backend logic powering parts of Shopify. 

Ecommerce development agencies can use Functions to do all kinds of exciting things, like changing the sort order for your store’s shipping and payment options, showing and hiding payment options, or even adding routing logic for how orders should be routed depending on specific conditions. 

There are tons of available Function APIs available publicly and in developer preview for an ecommerce agency to leverage to give your store the functionality your unique business requires to grow. 


In summary, Shopify checkout extensibility offers numerous benefits, including improved security, compatibility, and ease of customization compared to traditional checkout.liquid files. By partnering with an ecommerce agency, businesses can fully utilize checkout extensibility to optimize their checkout processes and provide exceptional shopping experiences for their customers.

As a certified Shopify Plus Partner agency, we at Blue Badger have the experience and expertise needed to ensure that your store’s transition from checkout.liquid to this new customization approach is smooth and easy. Contact us today for an audit of your checkout.liquid file or checkout extensibility implementation, extension installation or development, or backend customization with Shopify Functions today!  

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