Does Google Treat Subdomains as Separate Sites in 2018?

Those who practice SEO know that despite what Google claim, there's a difference.


If you’re seriously interested in ensuring that your website is performing well in search results, it’s important to understand how Google sees subdomains.

According to Google, they treat domains and subdomains the same, but those who practice SEO know that there is a difference.

Before we take a deep dive into this topic, let’s first look at what Domains are so that we are all on the same page.

What are domains and subdomains?

Domain names are the three-part, unique and human-friendly internet addresses of websites. They usually have an extension, a domain name and finally an optional subdomain.

First of all, know that the HTTP:// part of a URL is not part of the domain name, but it’s referred to as the ‘protocol’.

Let’s get deeper into the domain topic.

A top-level domain (TLD) is the name for the suffix that is located at the end of a domain name. For example, you may see these terms:

·         .com

·         .edu

·         .net

·         .info

·         .am

Although you may be familiar with most of the TLDs that are listed above, you may be surprised to know that there are now over one thousand TLDs from which website owners can now choose. These TLDs can be very descriptive and include names such as:

·         .book

·         .dog

·         .clothing

·         .am

·         .uk

·         .dk

The last couple of TLDs in the above list are country related, and you may know them as country code top-level domains – otherwise known as ccTLDs.

About domain names

After the top level domain, there is the domain name. They are purchased from registrars such as Go Daddy and represent the specific address or unique location of the website. For example there is:

Search engines do use any keywords that are used in domain names as part of their ranking system – which is why you’ll see domain names using keywords such as However, you do still need to consider whether you should optimise your root domain for SEO purposes. Google’s algorithm does penalise domains that are keyword stuffed.

Root domain

Originally named for DNS (domain name servers) the root domain is a combination of the top-level domain (otherwise known as an extension) and the unique domain name. It also happens to be the highest pages in the hierarchy of your website and will usually go to your homepage. Other pages and subdomains can be built off your root domain.

Root domains are unique, and no two websites can have the same root domain.


Finally, we are in the subdomain section. These are the 3rd level of the hierarchy of a domain and are usually added to the beginning of a domain name. For example, ‘’ is a subdomain of root domain. Subdomains are free to create as part of any root domain and separated by a full stop.

The two most common subdomain selections are:

these two subdomains can also cause canonicalization errors too.

The SEO best practices for domains

  1. Choose a branded domain name
  2. Use broad keywords or risk go
  3. Don’t use hyphens if you can help it
  4. Go for .com rather than any other suffix

Using a branded part-match domain avoids an “exact match domain”. Google no longer gives preference to exact match domains and it is no longer advised to use one because it’s very difficult to avoid over optimisation. Example “” is an exact match. This means we can’t easily use branded anchor text which would be “SEO Agency” as that’s a keyword. Instead, a part-match domain would be best. For example “;

So returning to the original question, despite Google claiming that they treat subdomains the same as a domain, even adding www puts your site into subdomain world. Each subdomain should be treated the same way that Disney treats their subdomains – like a separate business with their own relevant links.

If you want to know more about subdomains for your own website, contact us today for a no obligation chat about how we can help.