Short answer: track a page view, a meaningful engagement, a call-to-action click, a form submission and a qualified reply. Mark the form submission as a key event, and send the campaign source with it. Everything else is detail you can add later.

Why more events make reporting worse

A tracking plan with forty events usually produces reports nobody reads. Each event needs a name that survives a year, parameters that stay consistent and an owner who knows what decision it informs.

Start from the decision. If a report cannot change what you do next month, the event behind it is decoration.

The five

  • Page view, automatic when the tag loads.
  • Engagement, such as reaching the pricing section or spending real time on a page.
  • CTA click, one event per call-to-action location so you can see which section earns intent.
  • Lead submit, fired only after the form succeeds, never on button click.
  • Qualified reply, pushed back from the CRM or entered manually, so the funnel does not end at the form.

Send the parameters that answer the next question

An event without parameters tells you something happened. An event with parameters tells you what to do.

  • Campaign source and medium, captured on landing and stored for the session.
  • The page or section that produced the click.
  • The topic or service the enquiry is about.
  • The variant, if you are testing.

Google documents event and parameter limits in its event reference. Stay well under them; the limits are not the constraint, consistency is.

Mark one event as the key event

In GA4, conversions are configured as key events. Mark the lead submit and resist marking anything else, at least at first. Three key events means three definitions of success, which in practice means none.

If you run Google Ads, the import path and attribution behaviour are described in the conversions documentation.

Fire events after success, not intent

The most common error is a submit event bound to the button rather than to the response. It inflates the number and hides broken forms, because a failing form still reports leads.

Fire the event after the request succeeds. Fire a separate error event when it fails, and watch it: a form that silently fails on one browser is worth more to fix than any campaign optimisation.

Respect consent, and know what it costs you

If analytics only loads after a visitor accepts, your numbers under-report by the share of visitors who decline. That is correct behaviour, not a bug, but the baseline shifts the day you add a consent banner. Record the date and compare like with like.

Where to go next

Once events are trustworthy, decide where the money goes: splitting paid and organic budget. If third-party cookies are your constraint, read measurement without third-party cookies.

Need the tracking plan written and implemented? Book a fit call.