Impact of subdomain urls on SEO

Question

I have an application which is hosted on a subdomain URL of my client's primary domain. Below is the example of how my primary domain is and how the subdomain is:

• Primary domain: example.com
• Subdomain: replacephone-carriername.example.com

Now please help me understand below points:

1. Does my Primary Domain becomes my subdomain's competitor?
2. The carrier for which my client has created the application, has all the details of replacephone program and also this new application URL is linked into this carrier's main portal, and because of this, the carrier URL also becomes my subdomain URLs competitor, because we both are fighting for keyword say "replacephone-carriername" for different URLs.

Please advice me to encounter above 2 challenges.

Answer 1

Each page of your site should have a unique objective for ranking in searchers. Having that on mind, a unique title and content are needed in order to achieve that goal.

If you are ranking for the same keywords with the main domain and the subdomain you are doing something wrong (from an SEO point of view) cause, as you said, you are competing with yourself.

To prevent that situation:

• Make sure each page has unique title and content.
• Use internal linking to let searches know which are the "priority pages" of your site (the ones you want to rank for).
• Use structured data to let searchers know more about the purpose of each page.

Answer 2

Subdomains are considered separate domains from their parent domain. Google will indeed choose whether to rank replacephone-carriername.example.com or to rank example.com. So in a sense yes, they can be considered competitors of each other as they will rank separately.

If the content on the subdomain isn't as great as your main domain, you shouldn't expect it to rank over your main domain. This is especially the case if you have inbound links coming to your main domain and not to your sub.

If your subdomain has a rel follow link pointing back to the main domain, this will pass juice to the main. You may also want to add a nofollow link when linking the main site to the subdomain.

Overall, I wouldn't be too concerned about your subdomain ranking over your main domain. If and when that happens you can then use canonical tags, 301s and followed links to place priority to your main domain.

But for now if I were you, I would simply try to rank both the main domain and the subdomain. If Google sends your subdomain traffic that it wouldn't have sent to your main domain, it's worth it.