Should each subdomain be its own property in Google Analytics?

Question

I am auditing GA implementation for a startup and found they have a separate property for each of its subdomains. And yes, it is possible to navigate from subdomain to root domain and vice versa.

Each subdomain has a specific function as a blog or guide: (blog.example.com) and tools (tools.example.com) various tools user can use.

This is also true for Google Search Console as well.

Now the question is: is above setup correct? Since each property will have its own TrackingId how will this affect reporting?

Or should I just remove all subdomain property?

PS: I am using Google Universal Analytics and managing all of that with GTM.

Answer 1

There is no correct or wrong. It depends on how you want gather data, how many data is gathered, who has an access to which property and so on. Usually one makes a master property for the whole domain with all subdomains and one property à subdomain. This setup is easy to manage and it has clearly divided data. It looks like:

• Into GA-property UA-123456-0 one gathers data from the main domain https://example.com and all subdomains https://one.example.com, https://two.example.com, https://www.example.com, https://ww2.example.com
• To gather data from each of subdomains one creates own properties: UA-123456-1 for https://one.example.com, UA-123456-2 for https://two.example.com and so on.

It means:

• https://example.com sends stats to the one property, UA-123456-0
• https://one.example.com sends stats to two properties: UA-123456-0 and UA-123456-1

The same in the Search Console: one property for the whole domain, like *.example.com, and one property for every subdomain.

Answer 2

I personally go with the one property for all sites (domain, subdomain, alternate domain) and then use views to provide different ways of looking at them. e.g. all sites, each individual sites, a sub folder etc.

Doing this can be confusing as the default reporting does not include the domain (hostname) of pages. So reports covering multiple sites get a bit mixed up. You can add it a secondary dimension but that means constantly customising reports. Many people use a filter to make the path report the full URL for views that cover multiple sites.

Answer 3

I recently worked with a client who set up their GA they way you describe - although theirs was less deliberate and more messy.

I ended up adding a property which would record data from the entire site (what Evgeniy suggests above). It didn't replace their setup, it just extended it. So in the simplest terms, every sub-domain and domain of theirs reported back to their respective properties, but also back to one single property (needed to set up cross domain tracking). I did this mostly with GTM.

why did i do this?

I wanted to see traffic as it moved across the entire site. People were supposed to go visit the toolkit, the blog, their dashboard, etc, and I wanted to be able to manipulate, view, segment, and track behavior of all this data together. Frankly, I wasn't sure how I would do this with their setup.