GA4 setup: what to configure before you trust the numbers

Start with the questions, not the tag

The most common GA4 mistake is installing the tag first and asking what to measure later. Write the questions down before you open the admin screen. For most of our SEO clients they are short:

• Which organic landing pages lead to a form, a call click or a purchase?
• Which channels bring people who come back?
• Where do mobile visitors leave a checkout or enquiry flow?
• Did the last site change break any tracked action?

Every setting below exists to answer one of those. Anything that does not is left off, because each extra event is something to maintain and explain.

Property, data stream and tag

Create one property per business and one web data stream per domain you want to analyze together. Keep separate brands in separate properties unless you really need combined reporting. If you manage several subdomains of one site, a single stream with cross-domain settings is usually enough.

Install the tag with Google Tag Manager rather than pasting code into a theme. A container lets you change events without a developer release, and it gives you a version history you can roll back. For WordPress and Shopify sites we confirm that the theme, a plugin and the container are not all sending the same page view. Double-counting is the quickest way to ruin trust in the numbers.

Key events: a worked example

GA4 calls its important actions key events. Here is how we would name them for a service business with a contact form, a phone number and a booking calendar. Names are lowercase with underscores and stay stable forever.

Notice that most rows are not key events. If everything is a key event, no report separates the pages that produce enquiries from the pages that merely get read.

Settings that are easy to miss

• Data retention: the default for event-level data is short. Set it to the longest option so exploration reports can look back.
• Internal traffic: define your office and agency IP ranges, then switch the filter from testing to active after you have checked it.
• Unwanted referrals: add payment gateways and booking tools so a customer returning from checkout is not counted as a new visit from them.
• Cross-domain measurement: needed when a checkout or booking page lives on another domain.
• Google Signals and ad personalization: decide deliberately, with your privacy policy and legal advice in view.
• Channel grouping: check that your email and paid campaigns carry consistent UTM tags, or they land in Direct.

A filter set to testing does not remove any data. People often leave it that way for months and wonder why their own visits still inflate the numbers.

Consent and privacy by region

If you serve visitors in the EU, the UK or California, analytics has legal conditions around it. In the EU and UK, consent is generally needed before non-essential cookies or similar identifiers are set, and Google's consent mode lets tags adjust their behavior based on the choice made. California's CCPA and CPRA focus on notice and the ability to opt out of certain sharing.

The practical point for GA4: your consent banner, your container and your property settings must agree. If the banner says analytics is off until accepted, the container must really wait. We test this by loading the site in a clean browser, declining, and watching the network requests. Where the answer matters legally, your lawyer should confirm it. See also the GDPR website checklist.

Linking Search Console and testing

Link the property to the matching Google Search Console property so landing-page reports show queries and clicks next to sessions. The two tools count differently, as explained in our comparison of Search Console and GA4, so expect the numbers to differ and use each for what it does well.

Before sign-off we open DebugView, trigger every key event once on desktop and once on a phone, and confirm the event name, the parameters and the count of one. Only then do we mark the setup done.

Timeline

We have no separate published case study for analytics work. The part of our process that is documented is that SEO results are reported from the client's own Google accounts, so the property and Search Console access stay with you. For a quote, use the contact page.