There has been a pretty fierce debate in the SEO industry on the issue of subdomains versus directories, and in what kind of situation websites should use each kind.  But John Mueller made another interesting comment in the most recent Google Webmaster Office Hours.

The question was a longer complicated question about the use of subdomains versus a single domain with directories situation, and which would be best from both a technical and SEO perspective.

Many SEOs feel that subdomains can be stronger in certain situations, but also that they act somewhat separate compared to directories.  They are considered different properties in Google Search Console – essentially as individual websites , rather than a single one in a subdirectory situation.

During Mueller’s answer, he commented that Google is really good at being able to recognize a single website across multiple subdomains versus when it is multiple different (and often unrelated) sites across those multiple subdomains.

From my point of view, you can definitely use subdomains if that works better for you, go for it. That’s not something where I’d say you’d be worse off on subdomains.

We do try and understand the structure of the sites so if you have one normal website spread out across a lot of subdomains, which we sometimes see people have wildcard subdomains set up, then we’ll probably recognize it as one site, where as if we recognize that there are multiple sites running subdomains, we will recognize them as multiple sites.

So it’s not necessarily something where it always goes one or the other.

And don’t forget that using subdomains isn’t a way to aggressively SEO one section of a website, as manual actions given to subdomains can affect an entire site.

But this throws some more food for thought into the subdomains versus subdirectories argument, for those who weren’t aware of it.