Why you should consider avoiding Cross-domain tracking?

What makes online businesses successful is Digital Marketing. More specifically, Digital Analytics. Your ability to get feedback from your user to help you further improve your service or product to help them solve their problem, etc. must be efficient and make them happier. And as a result of their happiness, you will get compensated.

Why Digital Marketing or Digital Analytics or Google Analytics?

1. As business owners, we want to reduce risk. With risk, I mean avoiding wasting time, energy, and money, which are limited resources.
2. We want to control our time, energy, and money.
3. We want to grow our business as fast as possible by allocating our time, energy, and money in the best way possible.

But if you don’t strategically think about your digital analytics from day 1, you will have many problems reducing risk, controlling your business, and growing fast.

I am 100% sure that most business owners don’t enjoy wasting time, energy, and money.

Cross-domain tracking can lead you to waste time, energy, and money.


Why should you care about cross-domain tracking?

Although GA4 is making cross-domain tracking more straightforward, I would still recommend you avoid it whenever you can for the following reasons:
1. Safari, Brave, Edge, and Firefox all have serious tracking prevention against cross-domain tracking.
2. iFrame can make cross-domain tracking complex, and you might need technical skills to make the tracking smooth.
3. You didn’t set it up in Google Analytics.

So what is Cross-domain tracking?

Cross-domain tracking is

A way of allowing Google Analytics to track a visitor as a continuous session on two or more related sites, such as tracking www.siteA.com and www.siteB.com in the same GA Web Property.

An image which explains Cross-domain tracking

What are the results when cross-domain tracking, is not set up correctly or not even considered?

  1. A user that went from site A to site B where there is no cross-domain tracking will be reported as a new session.
  2. If the user starts on site A and then converts on-site B or vice versa, where there is no cross-domain tracking, your user journey is broken because GA will count it as a new session, which it’s not. So, conversion reporting can fall under source = direct & medium = none, or it can fall under referrals. It’s not what you are looking for.
  3. You won’t be able to understand how you’re getting your results and try to improve your business.


Which are the most use cases for cross-domain tracking?

  1. When you own multiple domains or site that are interconnected, and you want to understand the user across them.
  2. When you are using booking systems like Calendy, Clock, or any other where your user goes from your domain to another.
  3. When you have embedded iFrames on your website, for form submission or booking systems. HubSpot is an example.
  4. When you have an online education business, and you use your own website to convert users and a different website or platform to host the education stuff.

What are solutions to avoid cross-domain tracking?

The solutions are:

  1. Try as much as possible if you have multiple platforms to use subdomains (example: sub.domain.com). Anything that falls under your domain will come across as first-party tracking and not third-party tracking.
  2. Regarding booking platforms, try using booking systems that enable you to install Google Tag Manager on their platform and embed it on your website. You can then have two GTM accounts, where one will push the tracking data to the other. This push will help to maintain the tracking first party and avoid cross-domain tracking.

Subdomain explained:

A explanation of what is a subdomain

iFrame explained:

I will try to be less technical.
An inline frame (iframe) is an HTML code that loads another HTML page within the document. It essentially puts another webpage loading within a page.

I hope this video explanation gives you some clarification on iFrame and its tracking of it.

Check Julian’s blog post on iFrames tracking for a more detailed explanation.


Avoid cross-domain tracking to reduce the risk of wasting time, energy, and money.
If you have to work with other platforms, use only platforms that allow GTM integration or setup and embed them on your specific page. This will enable you to have first-party tracking through GTM and doesn’t break the user journey in GA.

Do you need help with the setup of iFrame tracking?