Google Analytics Audit: Our Detailed GA4 Audit Strategy

Introduction

At Versich, we work with finance and operations leaders who rely on clean, trustworthy data to make decisions every day. Google Analytics 4 (GA4) sits at the centre of that picture for most of our clients, feeding marketing dashboards, revenue attribution models, and executive reporting. The problem is that GA4 is rarely set up once and left alone. Tracking changes, new campaigns, website redesigns, and consent management updates all chip away at data quality over time.

That is why we built a structured GA4 audit strategy. Rather than a quick health check, our audit is a methodical review of how data is collected, configured, governed, and reported across your GA4 property. We designed it to catch the issues that quietly distort marketing ROI calculations, skew customer journey reporting, and undermine confidence in the numbers your leadership team sees.

We have run this audit process across e-commerce retailers, B2B software companies, healthcare organisations, and professional services firms. The businesses differ, but the pattern is consistent. Teams trust GA4 because it is the default analytics tool everyone uses, yet very few have ever had someone independently verify that what GA4 reports actually matches reality. A GA4 audit closes that gap before it turns into a costly decision based on flawed data.

In this article, we walk through how we approach a GA4 audit at Versich, the specific areas we examine, the common issues we uncover, and how the findings connect to broader analytics and reporting work, including the Power BI dashboards many of our clients use to bring GA4 data together with finance and operations data.

Why a GA4 Audit Matters

Many of the businesses we work with assume that because GA4 is collecting data, it must be collecting the right data. In our experience, that assumption is rarely true. GA4's event-based data model is fundamentally different from the old Universal Analytics structure, and a lot of configurations were carried over without being rebuilt for the new model. The result is data that looks complete on the surface but breaks down under scrutiny.

This matters more than most teams realise because GA4 data rarely stays confined to a marketing dashboard. It feeds budget conversations, board reporting, customer acquisition cost calculations, and increasingly, the same business intelligence tools used to report on revenue and operations. When tracking issues go unnoticed, they do not just distort a marketing report. They distort decisions that depend on that report, including how much a business spends on a channel, which campaigns get scaled, and how leadership interprets growth.

We typically see GA4 audits requested for one of three reasons:

• Leadership has lost confidence in marketing or conversion reporting because the numbers do not match other systems.
• A business is migrating analytics into Power BI or another reporting layer and needs GA4 data to be reliable before it becomes a feeding source.
• A website redesign, CRM change, or new campaign platform has gone live, and tracking has not been validated since.

Whatever the trigger, our view is the same: GA4 data quality is a prerequisite for good decision making, not an optional extra. We would rather a client invest in a thorough audit upfront than discover six months into a reporting project that the underlying data was never trustworthy to begin with.

Our GA4 Audit Strategy

We structure every GA4 audit around five core pillars. This keeps our review consistent across clients while still allowing us to go deep on the areas that matter most for a specific business model, whether that is e-commerce, B2B lead generation, or a subscription service.

Step 1: Reviewing Tracking Implementation

We start at the source. If the underlying tracking is wrong, every report built on top of it will be wrong too. Our team reviews the GA4 tag setup directly, usually through Google Tag Manager, and checks whether events fire correctly on the pages and actions they are meant to capture.

Specific checks at this stage include:

• Whether the base GA4 configuration tag is firing once per page load, not multiple times.
• Whether enhanced measurement settings (scroll tracking, outbound clicks, site search, video engagement) match what the business actually wants to measure.
• Whether custom events are passing the correct parameters, including transaction values, currency, and item-level data for e-commerce clients.
• Whether tracking is consistent across desktop, mobile, and any app properties feeding into the same GA4 stream.

We frequently find duplicate page view events, missing parameters on purchase events, and tags that were never updated after a website migration. Each of these issues directly affects the accuracy of revenue and engagement reporting.

We also test tracking under real conditions rather than relying solely on configuration review. This means using GA4's DebugView alongside browser-level inspection to confirm that events fire exactly as expected when a real user completes a real action, such as adding an item to a cart or submitting a contact form. Configuration screens can look correct while the actual implementation on the live site behaves differently, so we treat live testing as a mandatory step rather than an optional extra.

Step 2: Assessing Data Governance and Property Structure

A GA4 property that grows without structure becomes difficult to manage and easy to break. We review how the property itself is organised, including the number of data streams, how user access is controlled, and how data retention is configured.

• User and account permissions, to confirm access is appropriate and not overly broad.
• Data retention settings, since GA4 defaults often do not align with how long a business actually needs to retain event-level data.
• Custom dimensions and metrics, checking for duplicates, unused fields, and naming conventions that make reporting harder than it needs to be.

Good governance here also makes future audits faster, since a well-structured property is far easier to validate than one with years of undocumented changes.

We also look at how many people across the organisation have edit access to the GA4 property versus view-only access. In several engagements, we have found former employees or third-party agencies still retaining administrative permissions long after their engagement ended. Tightening this is a quick win that reduces the risk of accidental or unauthorised configuration changes going forward.

Step 3: Validating Conversion Tracking and Key Events

Conversion tracking is usually where the financial stakes are highest, and it is also where we find the most consequential errors. We compare the key events configured in GA4 against the business's actual definition of a conversion, whether that is a completed purchase, a qualified lead form, or a demo booking.

• Confirming that key events match real business outcomes, not just any button click that was easy to track.
• Checking attribution settings and the attribution model in use, since this affects how credit for conversions is distributed across channels.
• Validating that conversion values, where applicable, reflect actual transaction or deal value rather than placeholder numbers.

We have seen cases where a key event was left active after a promotional campaign ended, artificially inflating conversion counts for months. Catching issues like this is central to why this audit exists.

We also pay close attention to how conversions are counted for businesses with longer sales cycles, where a single customer journey may span multiple sessions and devices before converting. If user identification settings or cross-device signals are not configured correctly, conversions can be split across what GA4 treats as separate, unrelated users, which understates true conversion performance and makes channel comparisons unreliable.

Step 4: Checking Data Quality and Filtering

Even accurate tracking can produce misleading reports if the underlying traffic includes noise. We examine the filters and exclusions in place to keep the data representative of real users and real behaviour.

Step 5: Reviewing Reporting and Downstream Integration

GA4 rarely operates in isolation for the businesses we support. Most of our clients pull GA4 data into BigQuery or directly into Power BI to combine it with finance, sales, and operations data for a complete view of the business. We review how that data flows downstream and whether it is being interpreted correctly once it leaves GA4.

• Whether BigQuery exports are configured correctly and capturing the right event scope.
• Whether Looker Studio or Power BI reports are pulling from the correct GA4 property and date ranges.
• Whether metric definitions used in dashboards match GA4's actual calculation logic, since misunderstandings here are a common source of reporting disputes.

This is often where our GA4 audit work connects directly to broader analytics projects. Many of our clients ask us to take the cleaned, validated GA4 data and build it into a unified reporting layer.

If your team is already using or considering Power BI as your central reporting tool, our Power BI Consulting Services bring GA4, finance, and operational data together into a single, governed dashboard environment. For teams that already have Power BI in place but need ongoing support, our Power BI Support Services keep those dashboards accurate as data sources and business definitions evolve.

Common Issues We Find During a GA4 Audit

Across the audits we have run, certain issues come up repeatedly regardless of industry or company size. What stands out is that most of these issues are not the result of carelessness. They are the natural byproduct of a website and marketing stack that evolves faster than the analytics configuration supporting it. A new campaign tool gets added, a developer makes a quick fix under time pressure, or a redesign goes live without anyone circling back to confirm tracking still works exactly as before. The table below summarises the most frequent findings and the typical impact on reporting.

What We Deliver at the End of a GA4 Audit

We believe an audit is only useful if it leads to action. At the end of our GA4 audit engagement, we provide our clients with:

• A documented findings report covering each of the five audit pillars, with severity ratings for every issue identified.
• A prioritised remediation plan, ordered by the financial or reporting impact of each fix.
• Updated tracking documentation, so future changes to the website or campaigns can be implemented without breaking existing data collection.
• Recommendations on downstream integration, including how cleaned GA4 data should feed into Power BI or other reporting tools your team relies on.

Where clients want us to carry the work forward, we also support implementation of the fixes directly, followed by validation testing to confirm the corrected tracking is firing as expected in production.

We deliberately keep the findings report free of unnecessary technical jargon wherever possible, because the people who need to act on our recommendations are not always the people who manage the GA4 property day to day. Marketing leaders, finance teams, and operations stakeholders should be able to read the report and understand exactly what was wrong, why it mattered, and what we did or recommend doing about it.

Who Benefits Most From a GA4 Audit

We typically see the strongest return on a GA4 audit for organisations in the following situations:

• Finance and operations leaders who need marketing and revenue data to reconcile cleanly with other systems.
• Businesses preparing to consolidate analytics into Power BI for company-wide reporting.
• Marketing teams that have made significant website or campaign changes without revalidating tracking.
• Organisations going through a platform migration, such as moving e-commerce systems or CRM tools, where tracking dependencies are easy to overlook.

If any of these describe where your business is today, a structured GA4 audit is one of the highest-leverage steps you can take before investing further in analytics or reporting infrastructure. The cost of running an audit is consistently small compared to the cost of making strategic decisions based on data that was never validated in the first place.

Conclusion

A GA4 audit is not a one-time formality. It is a practical safeguard that protects the integrity of every report, dashboard, and decision built on top of your analytics data. At Versich, our structured approach across tracking implementation, governance, conversion tracking, data quality, and downstream integration gives our clients confidence that the numbers they are looking at actually reflect what is happening in their business.

We have found that businesses who treat GA4 auditing as a recurring discipline, rather than a one-off project, tend to catch problems within weeks rather than months. A short, periodic review after major website or campaign changes is far less costly than discovering a year-long tracking gap during a board presentation. Building that habit is one of the simplest ways to protect the credibility of your analytics function over the long term.

Whether you are trying to resolve a specific data discrepancy or preparing your analytics foundation for a broader Power BI reporting rollout, our team is ready to help. We also encourage you to explore our Power BI Consulting Services and Power BI Support Services to see how validated GA4 data fits into a complete reporting solution for your business.

To talk through your GA4 audit needs with our team, please visit our Contact Us page and we will be in touch to schedule a conversation.