GA4 Key Events: What to Mark and What to Skip

What a key event actually does

Marking an event as a key event tells GA4 to count it separately in a Key events column across the standard reports, and to make it available for attribution analysis. It does not change how the event is collected. The same event existed before you flagged it and keeps existing if you unflag it, though the history of the flag itself is not rewritten retroactively.

The flag also matters outside GA4. When you link GA4 to Google Ads, key events can be imported as conversion actions and used for bidding. That means a poorly chosen key event does not just clutter a report, it can teach an automated bidding strategy to chase the wrong visitors.

The test for a good key event

Before flagging anything, ask three questions. Does this action show real commercial intent? Does it happen a manageable number of times, rather than on nearly every visit? Would you be happy to pay for more of it? If the answer to any is no, it is probably a supporting event.

• Signal of intent: the visitor did something a customer would do, not just something a visitor does.
• Countable and distinct: one clear event per action, not a stack of overlapping events.
• Useful to optimize toward: you would accept ad platforms finding more people who do it.

Be careful about what you do with the counts. One quote request is not worth the same as one newsletter signup, and GA4 will treat them equally unless you assign values or keep them as separate, clearly named events.

Common events worth marking

For lead generation sites, the strongest candidates are a successful form submission, a click on a phone number, and a booking confirmation. Track the thank-you outcome rather than the button click, so a failed or blocked submission is not counted. On a service business built with WordPress, this typically means a form tool that fires an event on success or sends the visitor to a confirmation page.

For stores, the purchase event is the obvious one. Platforms such as Shopify and WooCommerce can send purchase data with transaction ID, value and currency. Check those fields are populated, because a purchase key event with no value tells you far less. Add to cart and begin checkout are better kept as ordinary events used in funnel reports.

Phone calls deserve special mention. A click on a tel: link is a signal of intent, not a completed call. If calls matter to your revenue, track the click as its own named event and consider call tracking in your ad platform for completed calls of a minimum length.

Events to leave unflagged

Page views, scrolls, outbound clicks, file downloads and video plays are useful context, but they rarely deserve key event status. A visitor who scrolled down a blog post has not yet shown buying intent. The same applies to engagement time thresholds and most button clicks.

There are exceptions. A downloadable price list or a spec sheet on a manufacturing site can be a meaningful micro action. If you do flag a softer action, treat it as secondary in your reporting, and keep it out of the list you send to Google Ads for bidding.

• Page views and session starts
• Scroll depth and engaged sessions
• Menu, tab and accordion clicks
• Generic file downloads such as terms or policy PDFs

Naming, counting and cleaning up

Use consistent, readable names such as generate_lead, phone_click or booking_confirmed, written in lowercase with underscores. GA4 event names are case sensitive, so Form_Submit and form_submit are two different events. Settle on a convention and write it down.

In the key event settings, choose how each event is counted. Counting once per event suits leads, where several submissions in a session should not inflate results. Counting once per session suits actions that are naturally repeated. Standard properties allow a limited number of key events, so the cap itself is a reason to be selective.

1. Open Admin, then Events, and review every event in the last 30 days.
2. Unflag any key event that fails the three question test.
3. Add a value to events where you can reasonably estimate one, such as an average lead value.
4. Verify each remaining key event with DebugView after a real test submission.
5. Review the list every quarter or after any site redesign.

Connecting key events to your ad accounts

Once the list is clean, importing it into Google Ads is straightforward. Import only the primary actions into bidding, and leave the secondary ones as observation. The same logic applies to other platforms: a Meta Ads campaign optimizing for a weak event will find people who perform that weak event.

If you are unsure how your events are currently set up, our Tag Manager and tracking work often starts with exactly this audit: what fires, what is flagged, and what is being sent to each ad account.