Approximately 38% of GA4 events on websites are misconfigured. If you have 10 conversion events in your GA4 property, 3-4 of them are likely broken - duplicating data, missing parameters, or being blocked by misconfigured consent mode. The result: you’re making business decisions based on data that’s wrong.

This article covers the five most common GA4 errors we find in our audits, how to identify them, and how to fix them.

Summary

  • Duplicate page_view is the most common error - it doubles all traffic data
  • Purchase events without revenue data make e-commerce reports show 0 in revenue
  • Consent mode misconfiguration can hide 40-60% of all traffic
  • Missing IP filters mix internal traffic with real customer data
  • Missing cross-domain tracking completely breaks the conversion funnel
  • A 15-minute quick check can reveal the most obvious errors

The five most common GA4 errors

1. Duplicate page_view events

The most common error we find. GA4’s Enhanced Measurement sends a page_view automatically, and then the GTM container fires another one. Result: every pageview is counted twice.

Symptom: Unreasonably high pageview numbers. Bounce rate that seems unusually low.

Fix: Disable “Page views” under Enhanced Measurement in the GA4 property, and let GTM handle page_view via a dedicated tag. Or vice versa - but never both.

Why it matters: All traffic data becomes unreliable. Landing page analysis, A/B tests, and channel reports are based on wrong numbers.

2. Purchase events without revenue data

E-commerce businesses that implemented the purchase event but forgot to send value and currency. GA4 registers that a purchase occurred, but doesn’t know what it was worth.

Symptom: Conversions show in reports but revenue shows 0.

Fix: Ensure the dataLayer sends value, currency, transaction_id, and items[] with every purchase event. Verify in DebugView that all parameters are present.

Why it matters: Without revenue data, you can’t calculate ROAS, identify profitable campaigns, or report actual returns to management.

Many websites have implemented Google Consent Mode v2 in a way that blocks all data collection until the user actively clicks “Accept.” With typical European consent rates (around 40-50% acceptance), this means the majority of traffic disappears entirely from GA4.

Symptom: Traffic in GA4 is dramatically lower than what server logs, Cloudflare stats, or other tools show.

Fix: Configure Consent Mode with the correct default settings (denied for ad_storage and analytics_storage, but with modeling enabled). Google can then model behavior for users who don’t consent, based on patterns from users who do.

Why it matters: Without proper consent mode configuration, it looks like your site has a fraction of its actual traffic. Campaign decisions are based on incomplete data.

4. Internal IP addresses not filtered

Your own team, your agency, and your developers generate traffic that mixes with real customer data. Every time someone tests a form, clicks through checkout, or browses internally, it counts as a real conversion.

Symptom: Conversion rate seems oddly high. Test orders appear in revenue reports.

Fix: Create an internal traffic filter in GA4 under Admin > Data Streams > Configure Tag Settings > Define Internal Traffic. Define IP addresses for your offices, home offices, and agencies. Then activate the filter under Data Settings > Data Filters.

Why it matters: Without IP filtering, internal testing can inflate conversion data by 10-30%, depending on team size.

5. Missing cross-domain tracking

Businesses with multiple domains - for example, a website on one domain and checkout on another - that haven’t configured cross-domain tracking. Every domain transition creates a new session in GA4, breaking the entire conversion funnel.

Symptom: High traffic marked as “referral” from your own domain. Conversion data that can’t be traced back to the original traffic source.

Fix: Configure cross-domain tracking in GA4’s tag configuration. Add all relevant domains under “Configure your domains” in Admin > Data Streams > Configure Tag Settings.

Why it matters: Without cross-domain tracking, your own pages appear as an external traffic source. The channel report becomes meaningless.

DIY quick check (15 minutes)

You don’t need to hire anyone to find the most obvious errors. Run this quick check:

  1. Open GA4 DebugView (Admin > DebugView) and navigate around the site. Check if you see duplicate page_view events on each page navigation.
  2. Test a conversion (purchase or form submission) - check in DebugView that purchase or generate_lead has value and currency as parameters.
  3. Compare traffic volumes - do the numbers in GA4 Realtime match what Cloudflare, server logs, or other tools show? A deviation of more than 30% suggests consent mode issues.
  4. Search for “(not set)” in GA4 reports - occurrences of “(not set)” in dimension reports are almost always a configuration error.
  5. Check source reports - do you see your own domain as a “referral” source? Then cross-domain tracking is missing.

If you find problems in more than two of these points, you likely have additional hidden errors that require a deeper review.

What broken tracking costs in money

Misconfigured GA4 tracking isn’t a technical problem - it’s a financial one:

  • Misallocated ad budget: You’re optimizing campaigns against incorrect data. Profitable campaigns get turned off, unprofitable ones get more budget.
  • Missed conversions: Events that never register make you underestimate what’s actually working.
  • Inaccurate management reports: Decisions at the leadership level are based on numbers that can deviate 20-40% from reality.
  • Regulatory risk: Misconfigured consent mode may mean you’re collecting data without valid consent. Sweden’s data protection authority (IMY) issued fines of 12 million SEK to Tele2 and 37 million SEK to Apoteket for data protection violations in 2025.

Real example: One of our clients had duplicate purchase events that made a Google Ads campaign look profitable. After we identified the problem in a tracking audit, it turned out the campaign was actually running at a loss. Wasted ad spend: 2,230 SEK per month, 26,760 SEK per year.

Frequently asked questions

How do I know if my GA4 setup has errors?

Open GA4 DebugView and navigate your site. Look for duplicate page_view events, missing purchase parameters, and “(not set)” values in your reports. If you find issues in two or more of these areas, you likely have additional hidden errors that require a professional audit.

What does broken GA4 tracking cost?

Misconfigured tracking leads to misallocated ad budgets, missed conversions, and inaccurate reports. A real example: one of our clients wasted 2,230 SEK per month due to duplicate purchase events - 26,760 SEK per year that would never have been found without an audit.

How often should you audit your GA4 setup?

At least once per quarter, and always after major website changes, GTM updates, or new campaign launches. Consent mode changes and Google updates can also affect data quality without you noticing.

What is the most common GA4 error?

Duplicate page_view events. This happens when both GA4’s Enhanced Measurement and a GTM tag fire page_view simultaneously. The result: every pageview is counted twice, distorting all traffic data and making landing page analysis unreliable.

Next steps

SOM Digital performs complete tracking audits covering GA4 configuration, GTM setup, consent mode, data quality, and event validation. We find the errors, prioritize them, and give you a concrete action plan.

Book a free strategy call - we’ll review your tracking and tell you exactly what needs fixing.

Peter is the founder of SOM Digital, specializing in GA4, server-side tracking, and tracking audits for businesses and agencies. Read more about our services.