E-Commerce Tracker

The full GA4 e-commerce funnel.

From initial catalog browse to issuing a full refund. Every micro-interaction is tracked.

E-commerce events to capture

view_item_list catalog loaded

select_item product clicked

view_item product page viewed

add_to_cart added to cart

remove_from_cart removed from cart

begin_checkout checkout started

add_shipping_info shipping info added

add_payment_info payment info added

purchase purchase complete

refund refund issued

GA4 e-commerce schema in 60 seconds

Every e-commerce event in GA4 follows the same shape: a top-level event with currency and value, plus an items[] array describing what was acted on. Here's an add_to_cart push as a reference:

dataLayer.push({
  event: 'add_to_cart',
  ecommerce: {
    currency: 'USD',
    value: 49.00,
    items: [{
      item_id: 'SKU_42',
      item_name: 'Halyk Hoodie',
      item_brand: 'Halyk',
      item_category: 'Apparel',
      price: 49.00,
      quantity: 1,
    }]
  }
});

Why this matters:

Use the exact event names GA4 expects (view_item, add_to_cart, purchase, etc.). Match the spec and GA4 enriches them automatically — no extra config.
items[] carries item_id, item_name, item_brand, item_category, price, quantity. Keep the keys consistent across every event in the funnel.
currency is mandatory. value is the sum across items. GA4 derives revenue from these two.
Set transaction_id on purchase to deduplicate. Pass it again on refund with the same id to credit the original transaction.

How to capture the funnel (catalog → cart → checkout)

Goal

One reusable tag pattern that handles every funnel step. You'll build six small tags using the same template.

Trigger

Custom Event · event name = view_item_list, select_item, view_item, add_to_cart, begin_checkout, purchase (one trigger per event name).

Tag

GA4 Event tag, event name = the trigger's event name. Add a single Event Parameter named items mapped to the Data Layer Variable ecommerce.items. Add currency and value the same way. Reuse this tag template across all six funnel events.

Verify

Click around the catalog → product → cart → checkout. In GA4 DebugView, you should see the funnel events fire in order with items populated. If items is empty in DebugView, your variable name doesn't match the dataLayer key.

How to capture purchase (the conversion event)

Goal

Mark this as the GA4 conversion. Pass transaction_id, value, currency, tax, shipping, coupon, and the full items[] array.

Trigger

Custom Event · event name = purchase

Tag

GA4 Event tag, event name = purchase. Map ecommerce.transaction_id, ecommerce.tax, ecommerce.shipping, ecommerce.coupon, ecommerce.items, currency, and value. In GA4 Admin → Events, mark purchase as a conversion if it isn't already.

Verify

Complete a checkout with the test coupon. DebugView shows purchase with all parameters populated. Re-run the same checkout with the same transaction_id — GA4 should ignore the duplicate. If you see double revenue, transaction_id isn't being passed correctly.

How to capture refund (and credit the original purchase)

Goal

Match the refund back to its original purchase using the same transaction_id, so GA4 subtracts revenue from the right transaction.

Trigger

Custom Event · event name = refund

Tag

GA4 Event tag, event name = refund. Pass transaction_id (must match the purchase), value, currency, and items[]. For partial refunds, only include the items being refunded with their refunded quantity.

Verify

Issue a refund from the order confirmation screen. DebugView shows refund. In GA4's Monetization report (give it ~24h), you'll see the original revenue net of the refund tied to the same transaction.