How does ecommerce event tracking work in GA4?

Tracking ecommerce events in GA4 is fundamentally similar to tracking other events. You set up tags or code to fire when specific events happen, then access the data in GA4.

GA4’s predecessor, Universal Analytics, used the Enhanced Ecommerce model for most ecommerce tracking. On July 1, 2023, standard Universal Analytics properties stopped processing data (360 properties had until July 1, 2024), which required the move to GA4. In GA4, ecommerce tracking is more integrated into overall event tracking, which makes it more flexible, and lets you get a fuller picture of what is happening on your site than UA did. Metrics and terminology also changed between UA and GA4, so it is worth checking Google’s comparison guide.

As with any GA4 setup, you can add GA4 code to your site manually, or use a tag-based solution like Google Tag Manager. This guide focuses on GTM. For the general event-tracking process, including setup without a data layer, see our GA4 event tracking guide.

How to set up GA4 ecommerce event tracking

This is the basic process with a data layer in use on your site.

1. Create a GA4 event tag in your Google Tag Manager container.
2. Configure the event tag with your parameters: enter a name in the left field and select the data layer variable with the relevant information in the right field.
3. In the event tag, add a trigger. In the event name field, enter the data layer event you want to fire the tag.
4. Click Preview and trigger the relevant events on your site. In the GTM preview pane, confirm the correct event data is captured and sent to GA4.
5. Publish your changes.
6. Test your changes after publishing, and on a regular, ongoing basis.

What types of ecommerce events does GA4 have?

There are four event types in GA4. Two are collected without extra code (automatically collected events, and enhanced measurement events when enhanced measurement is enabled), and two must be implemented (recommended events and custom events). Here are the ones most useful to ecommerce sites.

Automatically collected events. Tracked once the initial GA4 setup is done, with no extra steps, such as session_start, first_visit and user_engagement.

Enhanced measurement events. When enhanced measurement is enabled, GA4 also collects events such as page_view, scroll and view_search_results. The one ecommerce sites should watch is view_search_results, and you can optionally set site search to look for other URL query parameters.

Recommended ecommerce events. Commonplace events with predefined names and parameters, so they are relatively simple to implement, and where most ecommerce tracking happens. The ones likely to matter for an ecommerce site: login, purchase, refund, search, sign_up, add_payment_info, add_shipping_info, add_to_cart, add_to_wishlist, begin_checkout, remove_from_cart, select_item, select_promotion, view_cart, view_item, view_item_list, view_promotion.

Custom ecommerce events. For highly specialised needs you can create custom events, but this is more manual, because you provide your own parameters and triggers, and it is more prone to error, so it is best to rely on other event types where possible.

What product data can be tracked in GA4?

When setting up ecommerce tracking, you want data about the products customers buy, which shows your best sellers, popular categories, and how customers find particular products.

In GA4, product data is collected in a parameter called the items array. For an items array to function, one of these two parameters must be set:

• item_id, for example SKU_12345
• item_name, for example Camo Hoodie

Other significant item parameters:

• coupon: the name of a coupon associated with the item
• discount: the per-unit monetary discount for the item
• item_brand: the brand of the item
• item_category: item categories such as “Apparel,” “Adult,” “Hoodies.” You can set up to five item_category parameters, organised by hierarchy
• item_list_id: the ID of the list the item appeared in, such as “related_products” (item_list_name is the list’s name, such as “Related products”)
• price: the monetary unit price of the item

Beyond the required and recommended parameters, a standard GA4 property accepts up to 27 item-level custom parameters in an ecommerce event.

What are the key ecommerce events in GA4?

The most significant recommended ecommerce events, and how to track them:

• view_item_list. Fires when a user is shown a list of products, such as related items on a product page. Requires an items array, and can take item_list_id and item_list_name (not needed if set at the item level).
• view_item. Fires when a customer sees content about an item, such as its detail page. Requires an items array. A value parameter (for example 25.00) is needed for useful reporting, and setting value requires a currency parameter (for example AUD).
• begin_checkout. Fires when a user starts checkout. Like view_item, it needs value and currency plus the items array. You can also set a coupon parameter (item-level and event-level coupons are separate).
• add_shipping_info. Indicates a user added shipping information at checkout. Needs value, currency, and an items array, and can take a coupon and a shipping_tier (the selected shipping form, such as air or next-day).
• purchase and refund. Indicate a purchase or refund. Both use currency, value, coupon, transaction_id (a unique transaction identifier, for example T_12345), shipping (the monetary shipping value, not to be confused with shipping_tier), and tax. A purchase requires transaction_id and the items array. A refund requires transaction_id, and its items array is optional: send it for a partial refund.

What is the GA4 ecommerce purchases report?

Once ecommerce events are being sent, you can access a premade ecommerce purchases report, a good starting point for GA4 ecommerce.

It includes these dimensions: item brand (from item_brand), item category (the first hierarchical category, from item_category), item category 2 to 5 (from item_category2 and up), item ID (from item_id), and item name (from item_name).

And these metrics: item revenue (total revenue from items, excluding tax and shipping), items added to cart (from the items array in an add_to_cart event), items purchased (from the items array in a purchase event), and items viewed (from the items array in a view_item event).

GA4 ecommerce data and privacy

An ecommerce site handles personally identifiable information (PII), such as names, email addresses and card details. Google’s own policies prohibit sending PII, such as email addresses or phone numbers, to Google Analytics, so ecommerce and event tracking has to be set up to keep it out. Whether a given setup is compliant with the GDPR, the CCPA, or other laws depends on the data involved, your configuration, and the jurisdiction, which is a compliance question. For that, see the Privacy & Compliance resources.

Improve your ecommerce reporting with DataTrue

Optimising a GA4 ecommerce setup takes work, and you want to be sure you are collecting the best possible data. DataTrue’s data layer testing confirms this part of your setup is working, and its tag audit tools check the overall health of your tags with simulation tests, coverage tests, and validation maps. To understand the accuracy and integrity that ecommerce reporting depends on, see data accuracy and data integrity, and to check the tags themselves, the tag audit guide.

Confirm your ecommerce events fire with the right values

DataTrue tests your ecommerce journey step by step on your live site, checking each event fires with the right values, in each consent state. See how it works on the web analytics testing page.