On August 26, 2026, Shopify will remove access to Additional Scripts, Thank You page script boxes, and Order Status page scripts for all non-Plus stores. If you have Google Ads conversion tracking, Meta pixel code, or any custom JavaScript in those boxes, it all stops firing that day. No warning popup. No gradual sunset.
What Is Actually Changing?
Shopify is replacing its old script injection system with a structured, sandboxed framework called Checkout Extensibility. The old system let you paste raw JavaScript anywhere in the checkout flow. The new system gives you specific tools for specific jobs.
Here is what is going away and what replaces it:
- Additional Scripts (Settings > Checkout) are replaced by Web Pixels in Settings > Customer Events
- Thank You page scripts are replaced by Web Pixels that fire on the checkout_completed event
- Order Status page scripts are replaced by Order Status page extensions
- Shopify Scripts for payment and discount logic are replaced by Shopify Functions (deadline: June 30, 2026)
How to Check If Your Store Is Affected
Go to Settings > Checkout in your Shopify admin. Look for a yellow warning banner at the top. If you see one, your store has deprecated scripts that need to move before August 26.
Even if you do not see a banner, check your Additional Scripts box. If there is any JavaScript in there, it needs to move to Customer Events before August 26. This includes Google Ads conversion tags, Meta pixel purchase events, TikTok tracking, affiliate scripts, and any custom JavaScript you or a developer added.
Step-by-Step Migration Process
Step 1: Audit Everything (Week 1)
Before you touch anything, document every script running in your checkout. Go to Settings > Checkout and copy everything in the Additional Scripts box into a document. Check if you have any apps that inject scripts via script tags. Make a complete list of what each script does: conversion tracking, analytics, affiliate attribution, custom fields, etc.
Step 2: Set Up Customer Events (Week 2)
Go to Settings > Customer Events in your Shopify admin. This is where your tracking scripts will live going forward. For Google Analytics 4, install the Google & YouTube app from the Shopify App Store. It is compatible with Checkout Extensibility and will handle your GA4 conversion tracking automatically. For Meta (Facebook) ads, install the Facebook & Instagram app. It handles standard ecommerce events and CAPI (Conversions API) automatically.
If you are using other platforms (TikTok, Pinterest, Microsoft Ads), check the Shopify App Store for their official apps first. If no official app exists, you will need to create a Custom Pixel.
Step 3: Create Custom Pixels for Remaining Scripts (Week 2-3)
For any tracking that does not have an official Shopify app, you will need to create Custom Pixels. Go to Settings > Customer Events > Add Custom Pixel. Name it clearly (e.g., "TikTok Purchase Tracking"). Paste your tracking code and configure which events it should fire on.
Shopify Pixels run in a sandbox. They cannot manipulate the DOM or read page content. If you were using Google Tag Manager in your Additional Scripts, it will only work for conversion tracking in the new system, not for custom DOM-dependent tags or triggers. For GTM functionality on non-checkout pages, install it in theme.liquid instead.
Step 4: Test Everything (Week 3-4)
Place at least one real test order after migration. Use Google Tag Assistant to verify purchase events fire with the correct transaction value. Check your Meta Events Manager to confirm the purchase event is coming through. One common mistake: merchants migrate their Google tag but forget to map the revenue field. They run campaigns for weeks with conversions reporting at $0 value, which destroys their Smart Bidding performance.
Step 5: Disable Old Scripts
Once you have confirmed everything works in the new system, go back to Settings > Checkout and remove or comment out all code in the Additional Scripts box. Leaving both old and new tracking active will cause double-firing, which inflates your conversion numbers and ruins your ad optimization.
What About Custom Checkout Fields?
If you added custom phone fields, delivery notes, or special instructions through JavaScript injection, those will break too. The replacement is Checkout UI Extensions, but those require developer work and are primarily available on Shopify Plus. For non-Plus stores, look for apps in the Shopify App Store that provide checkout field functionality through the new extensibility framework.
Common Mistakes to Avoid
- Waiting until the last week. The entire Shopify ecosystem is migrating simultaneously. Developer availability will be scarce near the deadline.
- Copy-pasting scripts directly into Custom Pixels. The sandbox environment means old scripts may not work without modification.
- Forgetting about affiliate tracking. Many merchants focus on Google and Meta but forget their affiliate network scripts.
- Not testing with real orders. A preview or test checkout is not enough. You need an actual completed purchase to verify the full event chain.
- Leaving old and new tracking running together. Double-fired conversions will mess up your ad platform bidding algorithms within days.
Do You Need a Developer for This?
If your setup is simple (just Google Analytics and Meta pixel in Additional Scripts), you can handle this yourself using the official Shopify apps. If you have complex tracking setups, custom checkout fields, multiple ad platforms, or any server-side tracking, you should work with a developer who understands Checkout Extensibility.
I have been migrating stores through this process for clients and can handle the full audit, migration, and testing. If you want help, reach out here or check my checkout customization service.