GA4 Setup Guide: How to Ensure Reliable Insights

Google Analytics 4 (GA4) replaced Universal Analytics over a year ago, becoming the standard for website analytics. Most businesses now have a GA4 property installed. They might glance at basic traffic reports, see some familiar numbers, and assume everything is fine.

The hard truth? Most GA4 setups aren’t configured for real, actionable insights. Many are actively generating flawed data, leading to poor decisions and missed revenue opportunities.

GA4 isn’t an update; it’s a fundamentally different way of tracking data based on events, not sessions. Every click, scroll, form submission, and video play can be tracked individually, offering granular detail about how users navigate your site, where they encounter friction, and what truly drives conversions.

But unlocking these powerful insights requires proper configuration. Unlike its predecessor, GA4 doesn’t work effectively on autopilot. Relying on default settings or treating it like the old Universal Analytics often leads to inaccurate data, misleading reports, and significant blind spots. Common errors, sometimes made even by experienced teams, can range from double-counting revenue to missing crucial conversion points or even violating data privacy regulations. This uncertainty erodes trust in the data, hindering strategic decision-making.

This guide highlights the critical areas where GA4 configurations often go wrong and explains the potential business costs. Use it to assess whether your GA4 is a valuable asset or a potential liability.

Universal Analytics (UA) was built around sessions, grouping user interactions within a set time. GA4 focuses on events, tracking each interaction separately. This event-based model offers powerful capabilities:

• Granular Event Tracking: Every meaningful action can be recorded individually.
• Cross-Device Insights: Understand user journeys that start on mobile and finish on desktop.
• Enhanced Privacy Features: Better tools for compliance with GDPR, CCPA, etc.
• Predictive Capabilities: GA4 can leverage machine learning to estimate future user actions, like purchase or churn probability.

However, this shift brings challenges. GA4 has a steeper learning curve, and its flexibility means more opportunities for configuration errors. Essentially, GA4 requires an active, strategic setup. Simply migrating or accepting defaults often results in collecting data without the context needed for true understanding.

Before touching any GA4 settings, the most crucial step is strategic: clearly define what success looks like for your business online. Ask:

• What are the absolute key actions that drive revenue or leads? (e.g., Purchases, Demo Requests, Contact Form Submissions)
• Where do users typically abandon critical processes? (e.g., Cart abandonment, Form drop-offs)
• What specific data would empower better marketing or product decisions?

Why this matters: Skipping this foundational step is a common mistake leading to later significant problems. Without clear goals, you risk:

• Tracking Vanity Metrics: Collecting data that looks interesting but doesn’t inform strategy.
• Overwhelming Event Volume: Drowning in data from tracking too many irrelevant interactions, making analysis difficult.
• Misaligned Analytics: Your GA4 setup won’t accurately reflect the user journey or measure progress towards business objectives.

Action step: Identify the 5-10 most critical user actions for your business. These will form the core of your GA4 event and conversion tracking strategy.

Basic property settings seem simple, but errors here can undermine your entire setup:

Create or Migrate Your Property: While Google offered a GA4 Setup Assistant and even automatic migration, relying solely on these is risky. Manual verification is essential. Auto-migration sometimes created issues like duplicate tracking if not carefully managed.

Filter Out Internal Traffic: Your team’s visits can significantly skew data on user behaviour, session duration, and conversion rates. Failing to exclude internal IP addresses leads to flawed analysis based on inflated or distorted metrics.

Adjust Data Retention Settings: This is critical. By default, GA4 only keeps detailed user-level data for 2 months. This severely limits long-term analysis, year-over-year comparisons, and understanding seasonality, especially in the ‘Explore’ section. Many setups retain this default, unknowingly discarding valuable historical data needed for strategic planning. Change this to 14 months immediately.

Concerned about your foundational settings? A misconfigured property setup, like incorrect data retention or unfiltered internal traffic, can compromise all subsequent analysis. Our free 30-minute GA4 health check can quickly verify these critical settings.

Each platform (website, iOS app, Android app) needs a data stream. Key configuration points for websites include:

• Cross-Domain Tracking: Essential if users navigate between multiple domains you own (e.g., main site to a separate checkout domain). Misconfiguration breaks user journeys, inflates session counts, and wrongly attributes conversions to ‘Direct’ traffic. Verify that the _gl parameter appears in URLs when moving between domains.
• Site Search Tracking: Define your site’s search query parameters (e.g., ?s= or ?q=) to understand user intent.
• Enhanced Measurement: Automatically tracks scrolls, outbound clicks, file downloads, and video engagement. Review these settings – disable automatic scroll tracking if you use custom GTM triggers to avoid duplication.
• Referral Exclusions: Add domains like third-party payment gateways (e.g., PayPal, Stripe) to your referral exclusion list. Otherwise, conversions might be incorrectly attributed to the payment processor instead of the original marketing source.

Testing: GA4’s DebugView and Google Tag Assistant are used during setup, but interpreting the results accurately requires care.

GA4’s event-based model is its strength, but it’s also where many setups falter. Avoid these common pitfalls:

• Tracking Too Much or Too Little: Don’t track everything. Focus on the 5-10 key actions defined in Step 1. Tracking excessive, low-value events clutters reports, while missing critical interactions leaves blind spots.
• Inconsistent or Vague Naming Conventions: Event names like click_1 or submit_form_v2 become meaningless quickly. Use a clear, consistent schema (e.g., verb_noun like generate_lead or add_to_cart) and document it. Inconsistency fragments your data.
• Missing Custom Parameters & Dimensions: Events often need context. A purchase event needs value and currency. A button_click needs button_text or button_url. Crucially, these parameters must be registered as custom dimensions or metrics in the GA4 interface to appear in reports – a frequently missed step.
• Duplicate or Inconsistent Tracking: Errors can cause events to fire multiple times (duplicates) or not at all on certain pages (inconsistency). Duplicate tracking, common with e-commerce setups, inflates metrics like revenue and conversions, leading to wasted ad spend based on false performance. Inconsistent tracking breaks user journey analysis. Ensure tracking scripts (ideally via GTM) are implemented uniformly.
• Google Tag Manager (GTM) Complexity: GTM is the best practice for managing tags without constant developer input, but it requires expertise. Incorrectly configured tags, triggers, or variables in GTM are a major source of tracking errors.

Is your event tracking reliable? Inaccurate event data directly impacts your ability to understand user behaviour and measure marketing effectiveness. Our free 30-minute GA4 health check can quickly assess your core event setup for common, costly errors.

In GA4, any event can be marked as a conversion (now called ‘Key Events’ in the interface). This flexibility is dangerous if misused.

• Be Selective: Only mark the most critical events (identified in Step 1) that directly contribute to business goals as primary conversions (e.g., purchase, generate_lead, demo_booked).
• Distinguish Micro-Conversions: Track important but less critical actions (e.g., newsletter_signup, add_to_cart, pricing_page_viewed) as events, but don’t necessarily mark them all as primary conversions. Designating too many or low-value events dilutes focus and skews conversion reporting.
• Understand the Counting Difference: Unlike UA goals (counted once per session), GA4 counts every instance of a conversion event. Accurate setup is therefore even more critical for meaningful measurement.

Incorrect conversion configuration means you can’t accurately measure ROI or optimise campaigns effectively.

Integrating GA4 with platforms like Google Ads, BigQuery, and Search Console unlocks powerful capabilities but adds complexity and potential failure points.

• Google Ads: Linking allows importing GA4 conversions for smarter bidding and audience building. However, issues with linking or data syncing are common, preventing conversions or engagement metrics from appearing correctly in Ads.
• BigQuery: Exporting raw data enables deep, unsampled analysis, especially for large datasets. But ensure you understand potential discrepancies between GA4 reports and BigQuery due to processing differences or modelling.
• Search Console: Provides insights into organic search performance, driving site engagement.

Faulty connections, especially with Google Ads, can directly impact campaign performance and reporting accuracy.

Standard GA4 reports offer limited views compared to UA. The real analytical power lies in the Explorations section, allowing custom funnel analysis, path exploration, cohort analysis, and more. However, effectively using Explorations requires a solid grasp of GA4’s event-based model, metrics, and the tool itself. Many find it less intuitive than UA, making deep analysis challenging without dedicated learning or expert help.

GA4 offers advanced features like predictive audiences, custom dimensions/metrics for deeper segmentation (e.g., logged-in vs. guest users), anomaly detection, and custom alerts. However, these powerful tools are only effective if built upon a foundation of accurate, reliable data. Fixing the core setup must be the priority.

A well-configured GA4 setup is a powerful asset. It reveals what’s truly working, where users struggle, and how marketing efforts translate into results. Whether you run an eCommerce store, a SaaS platform, or a content-driven site, accurate GA4 data can help you:

• Reduce wasted ad spend by focusing investment on high-performing channels and audiences.
• Improve your user experience by identifying and fixing friction points in the user journey.
• Optimise conversion funnels by understanding where users drop off.
• Make strategic decisions with confidence, backed by trustworthy data.

GA4’s focus on first-party data empowers you to move beyond fragmented, less reliable third-party tracking and build a deeper, more accurate understanding of your customers. This richer understanding fuels strategic decision-making across various aspects of the business, from marketing and product development to customer experience optimisation. By leveraging the direct insights from their own audience. Learn how first-party data helps you build real connections with your customers.

Navigating Google Analytics 4 effectively is critical, but as highlighted, the path is fraught with potential pitfalls. An improperly configured GA4 collects flawed data, actively undermines business intelligence, leading to wasted resources, missed opportunities, and strategic missteps based on unreliable insights.

The core question remains: Can you confidently trust your GA4 data to guide your most important marketing decisions?
Stop wondering and start knowing. Eliminate the uncertainty and ensure your analytics platform is a powerful asset, not a hidden liability. Take the crucial first step towards data confidence by scheduling your FREE 30-minute GA4 Health Check. In just 30 minutes, we will review key aspects of your setup, identify potential red flags, and provide actionable feedback – all at no cost or obligation. Ensure your analytics are working for you, not against you.