Visit the Developer migration center for additional migration guides and resources.
The outcome of following this guide is that you will implement Google Analytics 4 ecommerce events for a new GA4 property and use that new implementation to populate your existing Universal Analytics reports. Your existing Universal Analytics implementation will be changed to receive GA4 ecommerce data.
Before you begin
Use the ecommerce migration helper tool to confirm that the following describes your current implementation:
- You are using a Universal Analytics property
- Your site uses the gtag.js library to send ecommerce events
Review the migration options for ecommerce implementations to learn about the trade-offs of each option. Confirm that you do indeed want to follow this guide to use Google Analytics 4 ecommerce events for your existing gtag.js Universal Analytics implementation.
Review the Event compatibility reference to learn how UA events are translated when sent to a GA4 property.
Trade-offs and considerations
Review and consider the information below to fully understand the implications of using Google Analytics 4 ecommerce events with your existing gtag.js (Universal Analytics) ecommerce implementation.
1. Update your ecommerce implementation
Update your existing ecommerce implementation to migrate from using Universal Analytics ecommerce events to Google Analytics 4 events. Once you've completed this step, your Universal Analytics property will be receiving GA4 ecommerce events. Review the Trade-offs and considerations to understand the implications of this update.
To assist with the update, use the following resources:
- The Google Analytics 4 Ecommerce guide to learn how to send GA4 ecommerce events.
- The information available in the Compatibility between UA and GA4 events and Comparable parameters for UA and GA4 tables. This information will help you map Universal Analytics ecommerce event names and parameters to equivalent events and parameters for Google Analytics 4.
- The ecommerce migration helper tool to validate you have updated your ecommerce events correctly.
2. Create and configure a new GA4 property
Once you've updated your ecommerce implementation to send GA4 ecommerce events, complete either of the following options to start sending data to a new Google Analytics 4 property.
Option 1: Use the GA4 Setup Assistant and enable connected site tags
The GA4 Setup Assistant will automatically create a new GA4 property and copy the following settings from your Universal Analytics property: property name, website URL, timezone, and currency settings. It can also enable the connected site tag feature to reuse your existing Universal Analytics gtag.js implementation to load your new GA4 property.
Follow the steps described in GA4 Setup Assistant to create and configure a new Google Analytics 4 property. Ensure you check the Enable data collection using your existing tags option to use the connected site tag feature.
Option 2: Update your gtag.js snippet
- Create a new Google Analytics 4 property.
- Use the GA4 Setup Assistant to add a Google Analytics 4 property. However, uncheck the Enable data collection using your existing tags option when prompted during setup. Alternatively, create a Google Analytics 4 property without the GA4 Setup Assistant. The advantage of using the assistant is that it will copy some basic settings from your Universal Analytics property.
- Find the tag ID for the Google Analytics 4 property.
- Add the Google Analytics 4 property to your existing gtag.js snippet using
configcommand with the tag ID.
The following is an example gtag.js snippet that has configured a Universal Analytics and Google Analytics 4 property:
<!-- Google tag (gtag.js) -->
<script async src="https://www.googletagmanager.com/gtag/js?id=UA-XXXXX-Y"></script>
window.dataLayer = window.dataLayer || ;
gtag('js', new Date());
gtag('config', 'UA-XXXXX-Y'); // Universal Analytics property
gtag('config', 'TAG_ID'); // Google Analytics 4 property