The GA4 setup checklist most accounts fail

Most GA4 properties were migrated in a hurry, left at defaults, and never revisited. The data comes out, people read it, and decisions get made on numbers nobody has validated.

Here's the audit I run on every new account.

1. Internal traffic is excluded

Admin → Data Streams → Configure tag settings → Define internal traffic.

Without it, your own team's sessions are in every report. For a small site with an active team, this can be a double-digit percentage of "traffic".

2. Cross-domain tracking is configured

If your checkout sits on a different domain, say a payment provider or a booking engine, and cross-domain tracking is not set, every conversion gets attributed to a referral from your own site. Your organic and paid channels end up credited with nothing.

This is the single most common cause of "our attribution makes no sense".

3. Unwanted referrals are excluded

Payment gateways, in particular. Without exclusion, a returning visitor from a payment page starts a new session with the gateway as the source.

4. Conversions are defined and actually meaningful

page_view on a thank-you page is a weak conversion. A dedicated event fired on transaction completion, with value attached, is a real one.

More importantly: mark as conversions only what you'd defend in a meeting. Ten conversion events means no conversion events.

5. Enhanced measurement is understood, not just enabled

Enhanced measurement auto-collects scrolls, outbound clicks, site search, and video engagement. All useful, but scroll fires at 90% depth and will inflate your engagement rate in ways that surprise anyone who does not know it is switched on.

Know what's on. Turn off what you won't use.

6. Data retention is set to 14 months

The default is two months. Two months means you cannot do year-on-year analysis in explorations, ever, on data you've already lost.

Admin → Data Settings → Data Retention → 14 months. Do this first, on every property, because it doesn't apply retroactively.

7. Google Search Console is linked

Admin → Product Links → Search Console. Gives you query-level data inside GA4 reports rather than in a separate tab.

8. UTM conventions are documented and enforced

facebook, Facebook, and FB are three different sources. GA4 is case-sensitive and will not merge them for you.

Write the convention down. Lowercase everything. Use a spreadsheet or a URL builder that enforces it. This is unglamorous and it prevents a category of reporting problem that is nearly impossible to fix after the fact.

9. A debug view test has actually been run

Before trusting anything: open DebugView, walk through the site as a user would, and watch the events fire. Confirm parameters arrive with the values you expect.

Almost everyone skips this. It takes fifteen minutes and catches most implementation errors before they contaminate a quarter of data.

The meta-point

None of this is difficult. It's all checkbox configuration in the admin panel.

It does not get done because analytics setup is nobody's job. It happens once during a migration, done by whoever happened to be free, and then everyone downstream assumes it was handled properly. Assume it was not, and go and check.