It feels like Shopify has been playing chicken with its Script deprecation timeline for the last few years. 

Originally, the platform announced that all users would need to migrate from Shopify Scripts to Functions by August 2024. Then, they announced that merchants would have an additional year to prep for the change, extending the deadline to August 2025. Well, August rolled around, and they once again pushed the deadline back to June 30th, 2026. 

That said, it looks like this summer’s deadline is the hard and final date, so if you’ve been dragging your feet when it comes to moving any residual Scripts over to Functions or leveraging other Checkout Extensibility-related customizations, now is the time. 

In this article, we’ll give you a comprehensive migration checklist – explaining what the change means, who needs to act, and a step-by-step plan to smoothly transition your checkout customizations to Shopify Functions so you don’t run into any unexpected problems when Shopify finally pulls the plug on those tiny pieces of code. 

Shopify Scripts vs. Shopify Functions – Differences and Why the Change?

Shopify Scripts are custom Ruby scripts that Shopify Plus merchants have long used to create advanced checkout discounts, shipping rules, and payment conditions. Shopify merchants loved Scripts because they allowed them to alter the output/behaviour of their shopping carts, making it easier to create more custom experiences for their customers, tailored to the unique needs and setups of their stores.  

In mid-2026, this legacy feature will be retired for good. 

Specifically, on June 30, 2026, all Shopify Scripts will stop functioning entirely, and starting April 15, 2026, you won’t be able to edit or add new Scripts. Shopify Functions, a newer solution running on WebAssembly (along with Shopify’s Checkout Extensibility upgrade), are the official replacement for Scripts. 

Depreciating checkout scripts is just one of the many changes Shopify is making as part of its push to get users up and running with Checkout Extensibility, its newer approach to editing the look and functionality of the checkout page.  

While a lot of functionality could be added to Shopify stores with Scripts, all implementation and changes needed to be made in the code editor. They were also isolated from newer Shopify features like Flow, GraphQL, and Checkout UI Extensions. This meant that not only did you need to keep a developer on hand for any updates or changes, but you were also unable to build Scripts that could fully integrate with the rest of the Shopify ecosystem and other apps via Shopify’s APIs. 

With the Shopify Script Editor deprecated, Shopify can focus on creating additional Function APIs to expand the already quite comprehensive level of customization its users can make to their checkout pages. 

Over the last few years, Shopify has been pushing towards a more app-based means of store customization. This makes it easy for merchants to install the functionality they need in their Shopify stores while opening up these tools, allowing developers to build any additional features they might need if they want something more complex or custom. 

Decision Framework: Planning Your Migration Approach

A Shopify Script to Shopify Function migration isn’t a one-size-fits-all process. Depending on what each Script does, you will often have a few paths to replace its functionality. 

Use this decision framework to determine how to recreate each Script in the new system:

1.  Use Native Shopify Features (No-Code): 

First, check if Shopify’s built-in features now cover what your Script does. Shopify has expanded discount capabilities in the admin. If a Script only provided a basic promotion that Shopify now supports out-of-the-box, you might not need a custom solution at all. Using native features is the simplest route and should be considered whenever possible.

2. Install a Shopify App (Pre-Built Function): 

Many common Script use-cases have already been implemented as public apps built on Shopify Functions. For moderate complexity needs like tiered pricing, bundle discounts, or wholesale pricing rules, check the Shopify App Store for Function-based apps. Shopify’s Scripts Customizations Report (available to Plus merchants) will even recommend specific apps for particular Scripts you have running on your store. 

3. Develop a Custom Function (Code Solution): 

If your Script’s logic is highly specific to your business and no app or native feature can replace it, you’ll need to build a custom Shopify Function. Custom Functions give you total control to replicate complex logic, but require developer expertise and maintenance. Only Shopify Plus stores can install custom Function apps that they or their partners build. 

Step-by-Step Shopify Scripts to Functions Migration Guide

Here’s your Shopify Scripts migration checklist for 2026: 

Step 1: Audit Your Existing Shopify Scripts

The first step in any migration is a full audit of what you have, so you can find out what you need. Start by taking inventory of all the Scripts running on your store. Identify what each Script does and whether it’s still needed. 

In your Shopify admin, go to the Script Editor and review each script. You can also use the Shopify Scripts Customizations Report, which automatically lists every active Script and its details.

Note the type (Line Item Script, Shipping Script, or Payment Script), determine its importance (or lack thereof), and consider if it's still relevant. Many stores will discover “ghost” scripts built for old promotions or edge cases that aren’t in use anymore at this stage. Anything that you don’t feel will be useful can be retired rather than migrated. 

Step 2: Map Each Script to a Replacement Solution

For each Script you intend to keep, decide how you will replace its functionality using the decision framework outlined above. For each Script:

1. Find the corresponding Function API or feature: Shopify provides specific Function APIs for the main Script categories. For example, a Line Item Script will map to the Discounts Function API, a Shipping Script maps to the Delivery Customization Function API, and a Payment Script maps to the Payment Customization Function API. 

2. Choose the approach (Native, App, or Custom): Mark whether each Script will be replaced by a Shopify admin setting, a third-party/public app, or a custom-developed Function. 

3. Use Shopify’s recommendations: the Scripts Customizations Report will link you to recommendations for apps that can replace your Scripts, as well as other guides that may be helpful. For example, if you have a Script that hides certain shipping options, the report might suggest a particular shipping rules app built with Functions or a tutorial on using the Delivery Customization API.

Consider creating a spreadsheet/table with columns like: Script Name/Description, Current Purpose, Migration Approach (App vs. Custom), and Notes/Recommended App or API. Once complete, you will have a clear idea of how each Script will be replaced in your new setup (and which won’t make the cut). 

Step 3: Recreate the Functionality (Implement Your Solutions)

Now, let’s execute your plan. First, install your Function-based app replacements for applicable Scripts. Follow the app’s documentation to configure equivalent rules, bundling, discounts, etc. At this point, you’ll want to make sure you’ve configured the app to match your old Scripts as closely as possible, reducing the chance of missing any important details. 

For Scripts with no off-the-shelf solution, you’ll need a developer to rebuild them as custom Shopify Functions. This involves creating a new Shopify custom app if you don’t already have one, and then using the Shopify CLI to scaffold a new Function extension. 

After installing an app or building a custom Function, integrate it with your store’s settings. Functions, whether via app or custom, will typically appear in your Shopify Admin under relevant sections. 

Double-check that each new Function or app is properly configured: for example, if it’s a Discount Function, is it active and targeting the right products/collections? If it’s a Payment customization, are the correct payment methods hidden or shown based on your rules? You might need to do some tweaking to ensure everything works properly before moving on to the next. 

Step 4: Test Thoroughly (Scripts and Functions Side by Side)

Before switching your old Scripts off for good, test your new solutions alongside the originals to confirm you’re getting the expected behaviour. Thankfully, Shopify allows you to run Functions and Scripts in parallel, so use this to your advantage:

1. A/B Test or Pilot New Functions: One method is to enable the new Function logic for a subset of orders or customers while keeping Scripts for others. For example, you can use a customer tag to control who sees the new Function vs. the old Script. Tag a test customer or a group of internal accounts so that when they go through checkout, the Function executes and the Script can be conditionally bypassed. Meanwhile, normal customers still experience the Script.

2. Verify Outcomes Match: During testing, run through all the scenarios your Script handled. Do you get the same discount applied? Are the correct shipping methods hidden? For each test order, confirm that the new Function replicates the intended behaviour of the old Script. Pay special attention to edge cases like combinations of products, high order values, or different customer tags, as this is where bugs often surface.

3. Performance and Stability: Keep an eye on checkout performance. One of the benefits of Functions is faster execution, so the checkout should be at least as fast as, if not faster than, the current checkout. Ensure that enabling the Function isn’t causing any errors. You can check Shopify’s logs or app logs for any Function error messages during tests.

Since Functions can be unit tested in development and then trialled in production on a limited basis, you have a nice safety net to catch any issues before the Scripts deprecation deadline. 

Step 5: Deploy Fully and Clean Up Legacy Scripts

If everything has been installed and tested successfully, you can now make the full switch to Functions. First, remove any and all test gating and activate the Function for all customers. Next, head into your Script Editor and unpublish or disable the old Scripts that you’ve replaced or decided that you no longer need. 

Keep a close eye on your store’s performance for a while after fully switching to Functions. Monitor metrics such as conversion rate, average order value, and checkout error rates. If you have analytics or reporting, compare data before and after the migration to identify any anomalies. Usually, a well-tested Function will perform equal to or better than the Script, but keep a closer eye on your post-migration metrics for a week or two afterwards, just in case. 

If anything does come up, use Shopify’s logs and your tests to debug. Since Scripts can run until the June 30th deadline, you can always re-enable them in a worst-case scenario. 

When to Bring in an Agency or Shopify Expert

As you may have already noticed, a migration to Shopify Functions can range from being rather straightforward to quite complex. Here are a few scenarios where involving a Shopify Partner agency like Blue Badger could be beneficial:

• No In-House Developer Expertise: If your team doesn’t include developers familiar with Shopify Functions, an agency can provide the necessary expertise.

• Complex or Critical Scripts: If you have Scripts that are overly intricate and/or essential to your revenue, you might need to bring on a team familiar with building complex Functions regularly to audit and provide support. When the logic is complex, the migration might involve writing and testing hundreds of lines of code. A Shopify Plus agency does this kind of work daily and can help you navigate the switch without breaking your checkout logic or product discounts/bundles. 

• Time Constraints: The clock is ticking towards the June 30th deadline, and if you’re starting to worry that you’ll have enough time to finish migrating your Scripts over to Functions, it might be beneficial to bring on an agency sooner rather than later. Remember – agencies will start to be booked out by other panicked merchants as the deadline gets closer. Engage a partner now to get ahead of the rush.

• Broader Platform Enhancements: Sometimes a Scripts-to-Functions migration is part of a larger modernization of your Shopify store. If you’re also considering a checkout redesign, adding new integrations, or overhauling your discount strategy, an agency can include a migration as part of a larger strategy. 

With something as important as migrating Shopify Scripts to Functions, bring on an agency if you feel unsure about any part of the upgrade. Even if you handle some aspects internally, an agency can take over the more complex tasks or simply review your plan.  

Frequently Asked Questions (FAQs)

Q1: When do Shopify Scripts stop working, and what happens if I miss the deadline?

A1: The Shopify Scripts deprecation will be complete on June 30, 2026. After that date, they will stop functioning. Shopify merchants will no longer be able to create new Scripts or exit existing ones after April 15, 2026. If you don’t act before the deadline, any custom discount, shipping, or payment logic you had via Scripts will simply not apply for customers. 

Q2: Can Shopify Functions replace everything my Scripts did?

A2: In almost all cases, yes. Every major use case of Shopify Scripts has an equivalent solution in the Shopify Functions ecosystem, even if it might not always be a 1:1 literal translation. Some migrations may use a combination of solutions, such as using an app for one part of the logic and a Function for another. As of 2026, there shouldn’t be a use case that can’t be handled via Functions in one way or another. 

Q3: Do I need to be a Shopify Plus merchant to use Shopify Functions?

A3: Using Functions is not limited to Plus in the same way Scripts were, but there’s a distinction between custom Functions and app-based Functions. Any store, even non-Plus, can install a public app from the Shopify App Store that includes Functions, but only Shopify Plus merchants can upload custom-coded Functions via a private/bespoke app. Simply put, if you want a tailor-made Function just for your store, you need to be on Shopify Plus. 

Q4: Can I run Shopify Scripts and Functions simultaneously during the transition?

A4: Yes. Shopify allows Scripts and Functions to coexist in your store until the cutoff. You can even run them in parallel on the same checkout for testing purposes. 

Q5: Can I handle the Scripts to Functions migration myself, or do I need a developer?

A5: It depends on the complexity of your Scripts. If your needs are simple and can be met with existing apps or built-in features, you might be able to handle the migration without writing code or by using Shopify’s native discount tools. If your Scripts involve complex logic unique to your business, you will likely need a developer’s help to create a custom Function or to customize an app.

Conclusion

If your Shopify Plus store still relies on Scripts, now is the time to audit what’s live, decide what should be replaced, and start migrating to Functions before you end up troubleshooting a broken checkout under pressure. Thankfully, this shift also provides Shopify merchants with a chance to simplify outdated customizations, improve performance, and build a more flexible checkout setup for the long term.

If your Scripts are complex or revenue-critical, Blue Badger can help you build and implement a migration plan that can save you a lot of stress and, more often than not, improve your checkout experience and functionality. Get in touch with us today to learn more.