GA4 key events: the setup that shows which channel paid

Everything in GA4 is an event: a page view, a scroll, a click, a form submission, a purchase. Marking an event as a key event tells GA4 to count it as an outcome and show it in acquisition and attribution reports, so you can see which channels and campaigns produced it.

The rename caused confusion because older guides still say “conversions”. In current GA4, you mark key events under Admin, in the Events or Key events settings. If you also want Google Ads to optimise towards one, you import or link it there, where it becomes a conversion.

A useful test: would your sales team or accountant care if this number doubled? Purchases, qualified leads and booked appointments pass. Scrolls, video plays and visits to the contact page do not; track them as normal events if you find them useful, but don’t mark them as key events.

GA4 limits how many key events a property can have, and a long list makes reports harder to read. Most small and mid-sized businesses need between two and five. Give each one a clear, consistent name so anyone reading a report knows what it means.

• generate_lead: successful enquiry form submission
• purchase: completed order with value
• click_whatsapp: tap on a WhatsApp link or button
• click_call: tap on a phone number
• book_appointment: completed booking

GA4’s enhanced measurement can record form interactions automatically, but in our audits it frequently counts form starts or submissions that failed validation. That inflates leads and makes the worst channels look good.

The most reliable method is a dataLayer push from the website when the form is accepted, picked up by Google Tag Manager and sent to GA4 as generate_lead. If that is not possible, use a thank-you page that cannot be reached directly, and exclude it from search engines.

Pass useful parameters with the event, such as form name or service type, and a value if you know roughly what a lead is worth. Never send personal data like names, emails or phone numbers to GA4; it breaks Google’s policies.

For many Indian businesses WhatsApp is the main enquiry channel, and without this tracking GA4 shows far fewer leads than the business actually receives. In Google Tag Manager, a click trigger on links containing wa.me, api.whatsapp.com or tel: covers most setups.

A click is not a lead. Some people tap and never send a message. Compare click counts with the conversations your team actually receives, and use a pre-filled message such as “Hi, I found you on Google” to help staff note the source.

Google Ads links are tagged automatically when auto-tagging is on, and Google Search Console can link with GA4. Almost everything else needs manual UTM parameters: utm_source, utm_medium and utm_campaign at minimum.

Agree a naming convention and write it down. “whatsapp / broadcast / diwali-sale” and “WhatsApp / Broadcast / Diwali Sale” appear as different rows in reports. Use lowercase, keep source and medium consistent, and keep a shared sheet of approved values.

Traffic acquisition is session-based: it credits the source of the session in which the key event happened, according to your reporting attribution settings. User acquisition shows the channel that first brought each user. Comparing the two shows which channels introduce people and which ones close.

GA4’s default reporting attribution is data-driven, with paid and organic last click available as an alternative. Whichever you choose, stay consistent month to month, and note that GA4 cannot see offline sales. For that, import CRM outcomes or send them back using the Measurement Protocol.