"Fourth-level" subdomains. Any negative impact compared with regular "third-level" subdomains?

[jamesm5i]

Hey moz

New client has a site that uses:

subdomains ("third-level" stuff like location.business.com) and;

"fourth-level" subdomains (location.parent.business.com)

Are these fourth-level addresses at risk of being treated differently than the other subdomains? Screaming Frog, for example, doesn't return these fourth-level addresses when doing a crawl for business.com except in the External tab. But maybe I'm just configuring the crawls incorrectly.

These addresses rank, but I'm worried that we're losing some link juice along the way. Any thoughts would be appreciated!

[Adam_Cochran]

If you check out Rand's Intro to SEO slideshare (http://www.slideshare.net/randfish/introduction-to-seo-5003433) slide 46 and 47 talk about URL structure and specifically sub-domains.

As Rob said you do want to sub-folder structures and avoid sub-domains. Hopefully you are old enough to remember when websites like lycos.com were big and people could make their own websites. These were all hosted on subdomains like moz.tripod.lycos.com and because of this structure search engines needed to see subdomains as separate websites. For this reason they have separate grading, change the flow of link juice and can easily count as duplicate content.

Sub-domains are best utilized for information that is distinct enough. Like in the moz example Rands personal blog could theoretically sit at rand.a-moz.groupbuyseo.org as its a separate theme, different content, etc it would just loose out on the  flow of value.

Once again Rob is right about using 301 redirects to move your subdomains into folders.

Now moving on to the more specific nature of your question "Are fourth level sub-domains any worse than third level sub-domains" I am going to suggest that when asking such a question you've already lost a big chunk of the SEO/inbound marketing battle.

The question you are framing is "I know it isn't good - but is it any worse?" Well even if it's not any worse you already know that it's not great and you should be taking structural steps to build on a sites accessibility, user functionality and it's SEO. If you find yourself asking "Is X any worse?" "How bad is Y?" "Can I get away with Z?" then you should immediately stop pursuing that idea and try and find a different method.

In this case that method is sub-folders and a 301 migration, but remember the framing of your questions and your over all directional strategy need to change to really drive home your campaigns!

[RobMay]

HAHA. Great. Thanks for the 'prop's. Going 4th and 5th level deep for sub-domains can also impeed the user experience when wanting to reach it directly (typing it manually is a pain!!)..

Thanks anyways, glad I could be of some help.

[jamesm5i]

Again - thanks a lot. I totally agree. Next client meeting I'll stress that not only do Ifeel strongly about the subfolder issue, but the good people at SimplifySEO feel the same:) And they know their ish. Or something.

[RobMay]

Stay away as much as possible for 4th, 5th and 6th level sub-domains, although I have never seen it go beyond 5. I would really try to emphasize the value of re-tooling the domain structure for long term benefits and linking. Keeping sub-domains running isolates link value and doesn't benefit the entire domain - thus making link building a much harder challenge. You are losing link 'juice' for every level of sub-domain used, as the value drops for each section of the domain that extends - hence the reason sub-folders are the way to go (as you already know)...

Good luck with the client and site. Sounds like a tough call. All the best and I hope it works out

[jamesm5i]

Hey Rob,

Thanks a lot for this. This is great advice and really well-written. And you're preaching to the choir. I also prefer subfolders, but it's just not in the cards for this client for the time being. As it stands, we're stuck with subdomains.

Any other thoughts re: fourth-level vs. third-level domains, folks?

[RobMay]

Hey there!

You should try to stay away from sub-domains, unless they really serve a purpose for the domain - then different strategies can be put into place. As I don't know if it's the route you need to take, I am going to proceed to give you an alternate option :).

1. You could always use sub-folders which in a nutshell would allow you to build links to the domain on many fronts and have them all count.

** NOTE: any links built to sub-domains don't flow link 'juice' to within the site. Those links build for whatever reason, will only pass value within that specific sub-domain.

2. What I would do, it replicate and migrate the structure of the sub-domains into the root domain of the site (www.site.com/subfolder1/ and 301 and rel-canonical all the sub-domain pages and structure to the new locations. That way, all link juice, value, etc already established is already kept in tact and just redirect all that value, trust and back-links to pages within the domain.

This to me is the best option to relocate the content, improve the domain structure using sub-folders instead of sub-domains, and maintain the back link profile already build (or existing) on the site/domain URL.

Other factors might affect reasons not to pursue this option, but I have always had success with this in large enterprise sites, when wanting to restructure the way domains handle sub-domains

Cheers!