How to Audit a Client's GA4 Property
in Under 5 Minutes

Every new client GA4 property is a black box until you open it. The previous agency may have left it in perfect shape. Or they may have left you staging traffic in production data, a payment processor stealing attribution, and conversion events that haven't fired in three months. You won't know until you look — and if you don't look before your first report, you risk presenting broken numbers as if they were facts.

This is the rapid triage process we've developed from auditing hundreds of GA4 properties. It won't replace a full audit. But it will tell you, in under five minutes, whether the data is trustworthy and where the most serious problems are. That's enough to walk into the first client call already knowing what needs fixing.

These three Admin settings take under a minute to check and tell you immediately whether the property has been configured with any care at all. Go to Admin → Data Settings → Data Retention and check all three in sequence.

If data retention is still at 2 months, change it right now before moving on. Every day it sits at the default is another day of data permanently lost. This single setting is the most commonly missed critical issue across every property we audit.

This one check tells you whether the data is contaminated with non-real-user traffic. Go to Reports → Tech → Tech Overview. Change the primary dimension to Hostname. Look at every domain in the list.

What you should see: only your client's production domain. What you often see instead:

Make a note of anything that isn't the production domain. Quantify the percentage of total sessions it represents. A property with 20% of sessions from staging has a 20% data quality problem — every single metric is wrong by some fraction of that.

Go to Reports → Acquisition → Traffic Acquisition. This single report surfaces three of the most common configuration failures simultaneously. You're looking for three things:

1. Unassigned channel is large

If Unassigned traffic represents more than 5–8% of sessions, something is wrong with how traffic is being tagged or attributed. Common causes are non-standard UTM medium values, missing UTMs on internal campaigns, or sessions from the payment processor issue identified in Step 2. Any Unassigned traffic above 10% is a serious data quality problem.

2. Payment processors in top sources

Change the primary dimension to Session source / medium. If you see paypal.com / referral, checkout.stripe.com / referral, or any payment processor in the top sources for revenue or conversions — attribution is broken. Your client's campaigns are getting no credit for the sales they're driving.

3. UTM medium variants

Scroll through the Session medium column. Look for casing inconsistencies: email and Email, social and Social, cpc and CPC. Each pair is a channel being split in two. Your client's email performance, social performance, and paid performance all look worse than they are.

Go to Admin → Events. Filter for events marked as conversions (the toggle in the "Mark as conversion" column). For each conversion event, note the last time it fired. This is visible in the event list as the most recent date in the activity log.

What you're looking for:

If your client has any EEA traffic — and almost every site does — Consent Mode v2 is not optional. Go to Admin → Data Display → Consent Settings. This shows whether consent signals are being received by GA4.

If the report shows no consent signals, or signals are present but only for a fraction of EEA traffic, there are two problems: a compliance risk and a data gap. Without Consent Mode v2, GA4 cannot model conversions for users who decline cookies — meaning EU campaign performance is underreported by 30–40% in many properties, and Smart Bidding for EU campaigns is optimising on incomplete data.

Make a note of the status and flag it prominently in your findings. It is one of the issues clients respond to most seriously because it has both regulatory and commercial consequences.

After five minutes, you should have a clear picture of the property's health across the five most commercially impactful areas. Not a complete audit — but enough to walk into the client call with authority.

The framing that works best in the client conversation is not "your GA4 is broken." It's: "before we can trust any of the numbers in your reports, we need to fix these specific things — here's what each one means for your data and your campaigns." That positions you as the expert who found the problems, not the person who delivered bad news.

The 60-second version of this entire process

The manual triage above takes under five minutes if you know where to look. But if you are onboarding multiple clients simultaneously, or want a comprehensive audit rather than a triage, GA4 Health Check runs all of this — and 41 additional checks — automatically in under 60 seconds.

You connect with your Google account, select the client property, choose a date range, and receive a scored PDF report with every finding prioritised by severity. The report is client-ready — you can hand it over directly or use it as the foundation for your own onboarding document.

For agencies running regular client audits, the 3-audit and 5-audit packs mean the per-audit cost drops significantly — and audits never expire, so you can use them as needed across your roster rather than on a fixed schedule.

See how GA4 Health Check works for agencies →

Travis Gunn

Founder of GA4 Health Check. Working with Google Analytics since 2013, with over 250 clients audited across almost every industry vertical. 100% Job Success on Upwork for over a decade.