GA4 does not automatically track conversions. Unlike Universal Analytics, which had Goals you configured, GA4 uses events as its base unit and requires you to explicitly designate which events are conversions. Getting this right is essential: the events you mark as conversions are what GA4 reports in its Conversions columns, what Google Ads uses for smart bidding, and what determines your reported conversion rate.
How GA4 Conversions Work
Every event in GA4 can be marked as a conversion. When an event is marked as a conversion:
- It appears in the Conversions column in GA4 Acquisition and Engagement reports
- GA4 tracks Conversion Rate = sessions with this conversion event / total sessions
- The event can be imported into Google Ads as a conversion action for smart bidding
GA4 automatically collects certain events (page_view, session_start, first_visit, scroll, click). You can add custom events via GTM or your tracking code. Any event — built-in or custom — can be marked as a conversion.
Which Events to Mark as Conversions for a Shopify Store
Essential
purchase: the ecommerce purchase event. This should always be a GA4 conversion. It feeds Google Ads smart bidding and is your primary business conversion metric. If you use Shopify’s GA4 integration or GTM, the purchase event should already be firing. Mark it as a conversion.
Optional (based on your goals)
begin_checkout: useful for funnel analysis and identifying checkout abandonment volume. Marking it as a conversion shows you how many sessions reached the checkout stage.
add_to_cart: useful for tracking top-of-funnel product interest. Do not use this as a Google Ads import conversion unless you intentionally want to optimise for add-to-cart clicks (usually not the right choice for ecommerce).
sign_up or account_registration: if you have a customer account sign-up flow, marking this as a conversion tracks how many users create accounts.
generate_lead or form_submission: for stores with a contact form or lead gen element, mark form submission events as conversions.
How to Mark an Event as a Conversion in GA4
In GA4, go to Admin → Conversions → + New conversion event. Type the exact event name you want to mark as a conversion (e.g. purchase). Click Save.
Alternatively, go to Reports → Engagement → Events. Find the event in the list. Toggle the “Mark as conversion” slider to the right for that event. This achieves the same result.
Within 24 hours, the event appears in your Conversions reports.
Common Conversion Setup Mistakes
Marking too many events as conversions
If you mark page_view, scroll, click, add_to_cart, begin_checkout, and purchase all as conversions, your conversion metrics become meaningless — almost every session will have a “conversion.” Keep your conversion events to the actions that represent real business value: purchase and a few supplementary events.
Importing the wrong event into Google Ads
When importing GA4 conversions to Google Ads, import only the purchase event (or your primary lead event) as the conversion action Google Ads optimises toward. Do not import add_to_cart or begin_checkout as the primary Google Ads conversion — the bidding algorithm will optimise for those events rather than actual purchases, usually reducing ROAS.
Not setting up revenue for the purchase conversion
When you import the GA4 purchase event into Google Ads as a conversion, configure it to pull the dynamic revenue value from the GA4 event (not a fixed average value). This allows Google Ads to calculate ROAS correctly for each individual conversion rather than assuming all purchases are worth the same amount.
Using the wrong event name
GA4 event names are case-sensitive. “Purchase” and “purchase” are two different events. The standard GA4 purchase event uses all lowercase: purchase. If your GTM tag fires a “Purchase” event (capital P), it will not appear in your list of events to mark as conversions alongside the standard “purchase.” Use all lowercase for all event names.
Verifying Your Conversions Are Working
After marking events as conversions and allowing 24 hours:
- In GA4, go to Reports → Conversions. You should see your conversion events listed with counts and revenue.
- Check that the purchase conversion count roughly matches your Shopify order count for the same period. If they are significantly different (more than 10%), investigate the discrepancy.
- Verify the revenue figure in GA4 Conversions roughly matches Shopify revenue (note: GA4 may not include cancelled orders or refunds automatically, so some difference is normal).
Book your free Shopify tracking audit here and we will review your GA4 conversion setup to ensure the right events are marked and your revenue data is accurate.