Subdomains vs Subfolders – Which to Choose?

For a lot of people, their websites evolve over time. You might start with a simple blog, then decide to add a section for your profession, then perhaps branch out into different services. Perhaps even language translations! Each time this happens, you need to make a structural choice about your new section. Is it going to be inside a subfolder or a subdomain? Over the years, this has generated much controversy amongst website developers, with strong opinions coming from both sides.

But in today’s world, the answer to that is a lot less contentious. Particularly when you take into consideration some of the quotations from John Mueller – Google’s de facto search relations liaison. So what should you do?

Two Segregation Possibilities: Subdomains and Subfolders

If you have a website called example.com, and you want to add a new blog to your existing hosting installation, you can designate it in two ways:

example.com/blog (subfolder)

or

blog.example.com (subdomain)

If you choose the first route, you might not even have to create a separate installation. If you’re using WordPress for example, you could just integrate a blog into your website from within the same instance and add a new menu item with the name “blog”. It’s easy!

Creating a blog on a subdomain on the other hand is a little more complicated. You first need to create the subdomain on your hosting account from cPanel, then install a new version of WordPress on that subdomain and create your blog that way. So the subfolder option is a lot easier, and the subdomain takes a bit of additional effort.

NameHero doesn’t restrict the number of subdomains you can create on any of the plans. Other web hosts, however, are not always this generous, and they restrict the number of subdomains you can use on their lower-tier plans. There’s never any limit on subfolders however.

The SEO Impact of Subdomains and Subfolders

Simply put, there isn’t any explicit difference between the two in terms of search engine ratings. There may be a contextual difference that I’ll explain below, but no hard and fast rule. This isn’t merely my opinion either. John Mueller himself is on record saying that Google treats these as the same for ranking purposes from a technical perspective. Here’s the full video in case you’re interested:

So according to John Mueller, there’s no difference.

BUT

Rankings Changes HAVE Been Observed – What’s Going On?

I’ve often said that Google’s advice can be misleading. There are well documented case studies of people moving content from separate subdomains to subdirectories, and obtaining a ranking bump during the process, even though they changed nothing else about the content.

Are you in need of 14 case studies to back up the assertion that:
Moving subdomain -> subfolder (almost always) increases search traffic
Moving subfolder -> subdomain (almost always) decreases search traffic
I got your back. Thread /1

— Rand Fishkin (follow @randderuiter on Threads) (@randfish) March 14, 2018

So what’s happening exactly?

The answer (once again according to Google), is that Google decides whether or not a new section is “part of the same site” – regardless of whether it’s a subdomain or a subfolder. If Google things “Yes, this new area is basically an extension of the same site”, then it inherits the parent site’s authority. Otherwise, it needs to build that authority on its own.

And That’s the Guideline – Relevance

Based on all this, we can finally string together a concrete recommendation. Use a subdomain if the new content is meant to be distinct from your existing site. For example, blogspot.com uses subdomains for all of its individual blogs that have no affiliation with the parent site. They’re all distinct content from the main blogspot.com domain name. You should follow the same guidelines for your own content.

If on the other hand, your new section is a supplement or an extension to your existing site, then you should put it in a separate subfolder instead of a subdomain, so that it can receive the page authority from the parent site and be ranked together as part of the same content.

I hope this clears things up! The actionable guideline described above should help you make an instant and easy determination of whether you should use a subdomain or a subdirectory for your site’s expansion!