Shopify Checkout Extensibility: How to upgrade your checkout from checkout.liquid to Checkout Extensibility


Chris Rausch


May 20, 2023

If you’re a Shopify Plus store owner, you’ve probably heard of Checkout Extensibility. As checkout.liquid is slowly phased out as Shopify’s checkout system, more stores are upgrading to the new system to help future-proof checkout and stay up-to-date on the best that Shopify has to offer.

Shopify Plus stores have the ability to upgrade from checkout.liquid to Checkout Extensibility now - and we’ll show you how to do it.

Not interested in upgrading your store yourself? Our Checkout Extensibility migration services can jumpstart your upgrade and build your next-gen Shopify custom checkout so that you can get back to selling better than ever.

Shopify Checkout Extensibility: the new checkout process

For nearly a decade, Shopify’s checkout system has been based around checkout.liquid. This theme file houses all of the code that defines the look, feel, and function of your checkout process. It can be edited directly by Shopify Plus stores or once Shopify unlocks it for you if you’re not a Shopify Plus store, but requires coding experience to make customizations effectively.

As of August 13, 2024, the checkout.liquid checkout process will be deprecated and replaced with Checkout Extensibility for all stores’ checkout pages. Post-purchase and order status pages will be unaffected for now.

Checkout Extensibility is the latest edition of Shopify checkout that is currently available to Shopify Plus stores. It aims to lower the barrier of entry for store owners customizing their own stores without the need for coding experience.

The Benefits of Shopify Checkout Extensibility

In addition to being required after checkout.liquid’s upcoming deprecation, Checkout Extensibility also offers a number of benefits when compared to the previous checkout system.

Shopify Checkout Extensibility is:


Your Shopify checkout process often needs a lot of customization to provide the ideal user experience. If you don’t have a developer handy to make the changes you need manually, you likely rely on apps to add the functionality or customization options that you need. However, due to checkout apps changing the code in your checkout.liquid theme file to work, you would no longer receive the latest updates Shopify made to the checkout.

Checkout Extensibility relies on apps, known as checkout extensions, to expand the capabilities of the new checkout system. In addition to a branding API that makes styling changes simple, you can install any number of extensions to add features like custom fields, calendars for scheduling orders, upsells and cross-sells, and many more features. Plus, the apps won’t directly impact the code of your checkout page, limiting the chances of something going wrong.


In addition to making it simpler for you to add the functionality you need to your checkout page, Checkout Extensibility also makes it easier to keep your checkout functioning throughout updates.

Previously, when Shopify or your apps received updates, there was a risk of the code in your checkout.liquid file being changed as well. When this happens, checkout processes could break - or you wouldn’t be able to enjoy the improved features and security of up-to-date apps.

With Checkout Extensibility, all apps are extensions of the checkout page, allowing you to make changes or update them without impacting the checkout page’s coding. It also means that Shopify updates can be installed without breaking checkout.


Checkout Extensibility makes it easier than ever for you to create effective, high-quality checkout experiences that drive conversions. 

The brand API allows for easy branding across all elements on your checkout page with minimal effort while the native customization tools provided by Checkout Extensibility allow you to style your pages without the need to edit code. Shopify Scripts also lets you easily implement logic into your checkout process that customizes user experiences for the best results possible.

To make it even easier, our upcoming release of Plus Checkout Customizer will extend the base functionality of Checkout Extensibility while adding customization tools that combine multiple other checkout apps in one simple interface.

How to upgrade from checkout.liquid to Checkout Extensibility

Now that you’re ready to move forward with creating a new checkout page with Checkout Extensibility, you’ll need to follow these steps to retain as much functionality as possible with as little downtime as possible.


If you have an existing checkout page, chances are that you have some customizations in place. If you want to retain these styling, branding, and functionality choices, it’s important that you do a manual review of both the visual elements and code of the page so that you know what needs to be added to the new checkout. It’s also a good idea to consult with a developer during this stage so that you can be sure all your customizations are tracked to avoid changes in the user experience.

First, review your existing checkout page either through your live site or by navigating to Settings > Checkout > Checkout Customization and selecting “view”. Make note of any colors or fonts that are used, elements that are added, logos and their locations, and anything else that makes your checkout unique. To make this easier, you can create a draft checkout under “draft checkouts” to see a default page that you can compare against.

After visually inspecting your existing checkout page, you’ll also want to review the checkout.liquid file for any customizations that you couldn’t see. You can find the checkout.liquid file under Online Store > Themes and then click the “...” next to your theme and select “edit code”, then find the checkout.liquid file. To make this easier, you can compare against the default checkout.liquid code using an online comparison tool.

Finally, once you’ve got all the customizations recorded, consider adding Shopify checkout extensions like UpsellPlus and Plus Checkout Customizer to help expand the functionality of your future checkout. You may also have existing Shopify checkout extensions that are already compatible with Checkout Extensibility which you can implement later.

Creating a draft

Once you’ve prepared all of the information that you need to transfer over to your new checkout page, it’s time to start building the checkout.

To begin, return to the checkout admin page by going to Settings > Checkout > Checkout Customization. Underneath your active checkout, you’ll see “Draft checkouts” where you can create a new draft. Select “Customize” to be brought to the checkout editor dashboard where you’re able to add any apps you have, edit branding, add tracking pixels, and more.

Review and publishing

After making all of your changes, you’ll be able to preview your checkout page as part of the checkout editor. Because your new checkout page is just a draft, you can compare it directly against your checkout.liquid checkout page to look for any customizations that haven’t taken effect.

Once you’re happy with how it looks, save your draft and return to the “Checkout customization” section, click on the “...” button on your draft, and select “preview”. This allows you to view your checkout as a guest so that you can ensure things run smoothly. If everything looks good, return to the previous screen and select “Publish” on your draft to make it live.

Be sure to test your new checkout page on multiple screen sizes and devices to be certain it works for all potential customers. You’ll also want to publish your new checkout during a slow period for your business to minimize disruptions.

Upgrade to the future of Shopify custom checkout with Checkout Extensibility and UpsellPlus

Whether you choose to upgrade to it yourself or work with us to migrate your existing checkout to Checkout Extensibility, it's essential to upgrade to the Shopify checkout process of the future. Checkout Extensibility is expected to be the future of Shopify’s checkout process for many years to come. It provides a number of usability, development, customization, and security benefits over checkout.liquid that makes it future-proof and the ideal choice for Shopify stores of all sizes - and Shopify checkout extensions make it even better.

With app integrations being such a major part of Checkout Extensibility, it’s important that you take advantage of all of the best checkout apps for Shopify to extend functionality so that you can achieve better results. Tools like Plus Checkout Customizer make it easier to create effective, high-converting checkouts, but an upsell app for Shopify Checkout Extensibility helps you make more out of each conversion.

UpsellPlus makes it easy for you to add a crucial element to your checkout process - upsells and cross-sells. With a simple offer builder that allows you to use logic and AI recommendations to create effective upsells and cross-sells plus testing tools so you can refine your process, there’s no easier way to grow your average order value and generate more income.

Best of all, UpsellPlus is available for Checkout Extensibility today - and try it out for 7 days for free. Get started today.

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