GA4 for E-commerce: The Essential Setup Checklist

GA4 is now the only version of Google Analytics. Here's what you need to set up for e-commerce tracking to work properly and what reports to look at first.

Why the Migration to GA4 Matters for E-commerce

Universal Analytics was retired in July 2023. GA4 is not just a rename — it’s a fundamentally different measurement model. UA was session-based; GA4 is event-based. Every interaction — page view, scroll, click, purchase — is an event, and events can carry custom parameters.

For e-commerce, this shift enables richer measurement: you can track individual products viewed, items added to cart, checkout funnel steps, and purchases with full order detail — all in a single unified data model.

The Non-Negotiable Setup Items

E-commerce events: GA4’s enhanced e-commerce tracking requires implementation of a specific event schema. The core events are: view_item, add_to_cart, begin_checkout, purchase. Each event needs item-level parameters: item ID, name, category, price, quantity.

Most major e-commerce platforms (Shopify, WooCommerce, Magento) have native GA4 integrations that fire these events automatically. Custom sites need developer implementation.

Conversion marking: In GA4, you mark events as conversions. At minimum, mark purchase as a conversion. For lead generation sites, mark your form submission event. Without this, your campaigns in Google Ads won’t have conversion data to optimise toward.

Google Ads linking: Connect your GA4 property to Google Ads in Admin → Product Links → Google Ads. This imports GA4 conversions into Ads and enables audience sharing between the two platforms.

Internal traffic exclusion: Add your own IP address to the exclusion filter so your browsing doesn’t inflate session and event counts. Admin → Data Streams → Configure Tag Settings → Define Internal Traffic.

Key Reports for E-commerce

Monetisation → E-commerce purchases: Shows revenue, transactions, and item-level performance. Use this to identify top and bottom performing products.

Acquisition → Traffic acquisition: Where are buyers coming from? Compare Paid Search, Organic Search, Direct, and Social by revenue and conversion rate — not just sessions.

Funnel exploration: Build a funnel from view_item through purchase to see where users drop off in your checkout process. A drop at add_to_cart suggests product page problems; a drop at begin_checkout suggests pricing or trust issues.

Path exploration: What do users do before they convert? Understanding the multi-touch path to purchase helps allocate budget across channels more accurately.

Connecting GA4 to Google Ads for Bidding

Once your GA4 purchase events are imported into Google Ads as conversions, you can use them as the optimisation signal for Smart Bidding strategies (Target ROAS, Target CPA). This closes the loop between your analytics and your ad spend.

Don’t run Target ROAS bidding off GA4 data until you have at least 30–50 purchase events per month in the account. Below this volume the algorithm doesn’t have enough signal and performance becomes erratic.

In Short

• GA4 requires e-commerce event implementation — view_item, add_to_cart, begin_checkout, purchase
• Mark purchase as a conversion and link GA4 to Google Ads
• Exclude internal traffic from day one
• Use Funnel Exploration to diagnose checkout drop-offs
• Need 30–50 purchases/month before Target ROAS bidding becomes reliable