A Simple Way To Set Up GA4 Cross Domain Tracking (And Impress Your Boss)

Brian Bojan Dordevic
About The Author

Brian Decoded

President at Alpha Efficiency

Join me at the forefront of web design and digital marketing innovation. I am obsessed with web design, business philosophy and marketing performance.
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Are you struggling to set up GA4 cross domain tracking? You’ve done this back in Universal Analytics, but the process has drastically changed with Google Analytics 4…

Your reports now feel disjointed. There’s nothing you can offer to your team. You’re losing control over user journeys across your company’s multiple domains. But what worries you the most is that your marketing strategies are missing the target. One after another. If this continues, you’ll get stuck with the average salary and the family to feed. And your boss’s look tells you that he expects this issue to be resolved today. The pressure is more than real.

But wait. Breathe. Let me tell you the good news:

Setting up cross domain tracking in Google Analytics 4 is actually MUCH EASIER than in Universal Analytics.

Anybody can do it.

No more messing with code or even opening Google Tag Manager. It’s all done within the GA4 platform. I found this a huge relief as a digital marketing agency owner dealing with clients and deadlines.

In this blog post, I’ll teach you how GA4 cross domain tracking works. Once you finish reading, you’ll know five simple steps you need to take to start collecting accurate data again. But data isn’t worth much without action, right? That’s why I’ll also show you how to impress your boss with insights you gain from cross domain tracking in Google Analytics 4. You’ll finally stop feeling like an imposter and deserve that long-awaited pay raise!

Table of Contents:
GA4 cross domain tracking.

The First Step To Success – Understanding Cross Domain Tracking in Google Analytics 4

We’ll get to the juicy parts later. First, let’s nail the basics.

What is cross-domain tracking, and why does your team leader keeps insisting on it?

In digital marketing and analytics, every user’s journey is a story you must understand and optimize. However, if a company uses multiple domains, it can be challenging to stitch together all the data from different websites and make sense of it.

Imagine you’re a marketing assistant for a thriving online store on “shop.example.domain.com.” To amplify your company’s reach, you suggest running a blog on “shop.blog.example.domain.com” discussing the latest fashion trends. What an excellent idea. Your articles will contain anchor links seamlessly guiding readers to your main store.

This sounds perfect, in theory. But that’s where the problem arises…

Why is having multiple domains without cross-domain tracking a reason for concern?

By default, Google Analytics 4 (GA4) assigns unique identifiers to users through first-party cookies when they land on a domain. This works perfectly as long as users stay within a single domain. But when they decide to hop from one domain to another? A huge problem…

Without the proper cross-domain tracking, every user transitioning from your blog to your online store might be perceived as a new, unique visitor. Your user count will appear higher than it actually is, distorting your insights.

Making decisions based on inflated user counts is dangerous. You’ll never truly understand your audience this way. And that’s why you’ll inevitably make mistakes. Others will think it’s solely your fault. They’ll think you’re not capable of making rational, data-based decisions. That hurts… Especially when you were just trying to follow the story data told you.

GA4 Cross Domain Tracking Helps You Connect The Narrative

Cross Domain Tracking in GA4 acts like a bridge between your domains. It helps you seamlessly track a user’s journey from one domain to another. Instead of treating a person who moves from one of your domains to another as two separate entities, GA4 will now understand them as one continuous user. This means that you’ll be able to preserve their session information across both domains.

The Perks?

  • Complete User Journeys: Gain accurate insights into the complete journey of a user, from reading your blog post to making a purchase on your online store.
  • Optimized Marketing Strategies: By understanding the holistic behavior of a user, tailor your marketing strategies effectively, ensuring higher conversion rates and ROI.

I’ll show you more benefits later in the article. Now, let’s discuss another burning question…

Why You SHOULDN’T Set Up Cross Domain Tracking For Subdomains?

As a Google Analytics consultant, my clients often ask me if they need to set up cross domain tracking in GA4 for their subdomains. A good question!

But the answer is NO. Setting up GA4 cross-domain tracking for subdomains will only waste your time. And if anyone from your team sees this, they might think you’ve not done your homework.


Because Google Analytics 4 automatically collects data for your subdomains. You don’t have to set up subdomain tracking on your own.

So if your company has the main domain (let’s name it “shop.example.com”) and several subdomains (we can call these “blog.shop.example.com” or “support.shop.example.com”), you have nothing to worry about. The data you’ve been collecting so far is not inflated. Google Analytics 4 automatically created measurement cookies for your main domain and used them for tracking subdomains too.

You’ll find this guide useful only if your company owns multiple website domains and the team expects you to set up GA4 cross-domain tracking for these.

Benefits of using cross domain tracking in GA4.

You Can Impress Your Boss With GA4 Cross Domain Tracking – Here’s How

Even if your GA4 cross domain tracking is working correctly, it won’t mean much if you don’t take action based on the data you gather.

In reality, cross-domain tracking is just a tool. And your boss probably only cares about the end results. The fact that you’ve properly set up cross-domain tracking won’t mean much when negotiating a new salary. But the ROI you secure for the company can be a strong argument. 

That’s why, in this section, I’ll show you the following:

  • Simple ways to use data you collect across multiple domains to make your marketing strategy more effective. This gives you confidence when negotiating a salary.
  • How you can prove your value to everyone on the team with precise marketing ROI calculations. You’ll know how effective every dollar you spend really is.

There are many Google Analytics 4 benefits. Once you get comfortable with this platform, it becomes clear that it’s superior to its predecessor. 

Boost Conversion Rates For Your Company By Polishing User Journeys

As a marketing manager, one of your duties is to ensure a smooth user journey between the company’s multiple website domains.

Let’s say you’re working for an eCommerce business. You’ve been tasked with ensuring that users who begin their journey on your blog, “read.and.shop.example.com,” effortlessly transition to making purchases on your online store, “buy.and.shop.example.com.” But how can you ensure that the user’s experience isn’t fragmented between the two domains if you can’t collect accurate data?

GA4 cross domain tracking helps you closely monitor customer behavior as they hop between domains. You can note their every movement, every interaction – with laser precision. You’ll gain insights into their preferences and potential points of drop-off.

Paired with GA4 custom dimensions, cross-domain tracking becomes an even more potent tool. This combination helps you collect data tailored to your needs and share knowledge with your team to increase sales.

For example, you can segment your visitors with tags like “sustainability enthusiast” or “summer fashion” based on blog posts they read on the first domain. And then, when they transition to your shop domain, you can show them exactly the offers they’ll be most interested in. Boom… They now don’t have to scroll through all the offers. You’ve minimized the roadblocks on their path to conversion – a critical thing to do in the fast-paced online environment. 

But the cherry on top?

When you’re able to show your boss that you’ve leveraged cross-domain tracking to boost profit significantly – you’re not just going to earn a pat on the back. You’ll have tangible proof of the value you bring to the company. No more sweating before performance reviews. You can now negotiate a better salary with confidence.

No More Wrong Assumptions and Wasting Budget Thanks to Accurate Marketing ROI Calculations

Ever felt that nagging doubt if your marketing dollars are truly driving the results you want? You’re not alone. Today, user journeys are more complex than ever. There are usually multiple interaction points, and understanding the full spectrum of a user’s journey is quite challenging. Without cross domain tracking in Google Analytics 4, you might be blindsided. It’s easy to overlook the value of primary touchpoints as users move between domains.

Let’s say you specialize in digital marketing for doctors (the same principles apply to any industry). Your clinic holds webinars and writes insightful articles about heart health on the clinic’s primary website, domain A.

Meanwhile, the clinic has a telehealth platform on domain B, where patients can book consultations after reading your content.

A potential patient stumbles upon one of your clinic’s articles, gets convinced of your doctor’s expertise, and then proceeds to domain B to schedule an appointment. Without cross-domain tracking, the initial touchpoint – that article on domain A – might not get the credit it deserves. You might conclude that the telehealth platform alone drives all the traffic and conversions.

By employing cross-domain tracking, you can pinpoint each step potential patients make before scheduling an appointment. This precise data allows you to:

  • Optimize campaigns with precision
  • Allocate budgets more efficiently
  • Truly grasp the ROI of every marketing effort

When you link domains, you gain a 360-degree view of conversion pathways. This helps you sharpen your marketing ROI calculations. You can track users as they navigate between your websites and ensure that every dollar you invest in various channels delivers results. Your team will love your insights again and appreciate the value you bring.

9 Steps to set up GA4 cross domain tracking.

How To Set Up GA4 Cross Domain Tracking (in 9 SIMPLE Steps)

Now that we understand what cross-domain tracking is and why it might be essential for your company, it’s finally time for me to show you how to set things up.

The evolution of web analytics has taken a massive leap forward with Google Analytics 4. If setting up cross-domain tracking used to frustrate you, you’re in for a treat. This has become much easier in GA4. Let me explain a step by step process to set up cross-domain tracking in GA4:

Preparation Step:

Before you begin, ensure you’ve installed the same GA4 property on all sites you want to track. Both websites involved must share the same measurement ID.

Step 1: Navigate to GA4 Admin

Start by logging into your Google Analytics account. At the bottom left corner of the dashboard, click on “Admin.” This will grant you access to the administrative settings of your analytics property.

Step 2: Access Data Streams

Within the Admin section, under the “Property” column, find and click on “Data Streams.”

Step 3: Choose Your Web Data Stream

On the screen’s right side, you’ll see all the data streams linked to your account. As you’re setting up for websites, click on “Web” and then select the data stream related to your site.

Step 4: Head to ‘Configure Tag Settings’

Scroll to the bottom of the data stream page and click “Configure tag settings.”

Step 5: Proceed to ‘Configure Your Domains’

You’ll now see an option that says “Configure your domains.” Click on it. 

Step 6: Add Your Domains

Here, you must decide which domains you wish to include in cross-domain measurement. Click on “Add condition.”

Step 7: Define Match Type

In the dropdown menu for “Match type,” choose “Contains.”

Step 8: Insert Your Domain

Type in your domain in the “Domains” box, excluding the ‘www.’

Step 9: Save and Repeat

After entering your first domain, click “Save.” If you have additional domains you want to set up GA4 cross-domain tracking for, repeat Steps 6 to 8.

That’s it! You’ve successfully set up cross domain tracking in GA4. It’s also a good idea to use annotations in GA4 to remember the date GA4 started tracking website visitors across your multiple domains. 

But before letting your team know that they can rely on the GA4 data again, there’s one more step I strongly recommend – testing your cross-domain tracking setup.

The Best Way to Test the Cross Domain Tracking GA4 Setup

Confirming you’ve correctly set up GA4 cross domain tracking will help you prevent potential data inconsistencies and lost user journey insights.

Don’t worry; it’s pretty simple.

You can test cross domain tracking either by manually checking URLs or using a Google Analytics Debugger Chrome extension.

Simple way – Inspect the URL manually:

I first suggest waiting for at least 5 minutes after saving your configurations. This will give GA4 enough time to process the changes you’ve made.

To begin the testing process, access the main website where your analytics tracking is set and click on the link that redirects users to the secondary website just like your visitors would.

Upon landing on the second website, inspect the URL. Tracking works perfectly if you notice a “_gl=” parameter filled with cookie information.

In-depth way – Use Google Analytics Debugger:

If you want a more in-depth verification, you can use the Google Analytics Debugger Chrome extension and follow these steps:

1. Visit the DebugView in GA4: Within GA4, navigate to the DebugView section. This panel displays real-time data, making it easier to trace your actions.

2. Track the Page View Event: Return to the primary website and refresh. In DebugView, a ‘page_view’ event will pop up, mirroring your site visit.

3. Evaluate Important Parameters: In the DebugView report, click on the ‘page_view’ event to pull up its details. Two essential elements to check are:

  • ga_session_id: This unique identifier should remain consistent across both domains, proving that the session data is being maintained.
  • page_location: While initially showing the primary domain, this parameter should reflect the secondary domain’s URL once you click the redirecting link element.

4. Consistency is Key: Ensure the ga_session_id remains unchanged when transitioning between domains. This proves that user visits across websites are counted as a single, unified session. Meanwhile, the page_location should rightly vary, showing the current domain the user is on.

Boost Your Career By Mastering Google Analytics 4

Has your company recently started using Google Analytics 4? That came as a surprise… Everything felt so comfortable in Universal Analytics. The whole team relied on your insights. But now you don’t even know where to start learning.

Feel that nagging sensation? That’s your boss watching. He heard how other marketers are already using Google Analytics 4 to drive profit, and he expects NOTHING less from you. You can’t help but feel paranoid. If you don’t adapt quickly, your whole career might be in danger. That would crush your dreams of providing more than an average life to your family.

As someone who makes a living from marketing, I also dealt with the pressure of learning GA4 quickly.

But this platform felt so complex…

Until I connected all the dots.

I realized how you can use GA4 to make your campaigns effective.

Learning GA4 on your own inevitably leads to a trial-and-error process. If you have much to spare, that’s okay. But if it’s burning under your feet… You’re still not stuck! As a Google Analytics consultant, I’d love to help you start using GA4 like an expert – FASTER than your colleagues. My clients are using things I teach to impress people in their companies. You’ll start gaining insights from Google Analytics 4 like never before. A whole new dimension will open up in front of your eyes. And once you start using Google Analytics 4 like a PRO, you’ll be able to finally convince your boss that you deserve a bigger salary! Most of my clients, who feared GA4 before, have now boosted their careers thanks to this platform.

You can start today by scheduling a free call with me. We will discuss your needs and how I can help you solve the challenges in front of you. And don’t worry about your busy calendar. We’ll tailor the consulting plan and sessions to your own preferences!


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