Blog | Vanguard 86

Subdirectories vs. subdomains for blogging: which is better for SEO?

Written by Dylan Burrows | 23-May-2025 02:15:48

Lately, one question that keeps popping up is: 'Should I use a subdomain (example.yourwebsite.com) or a subdirectory (yourwebsite.com/example) for my blog to improve its SEO?

The subdirectory vs. subdomain debate has been around for years. Some SEO specialists are against using subdomains, while others argue it doesn’t make much of a difference at all. 

However, it’s completely understandable to want to know which option is best for your business.

Content marketing remains one of the most effective ways to attract inbound traffic, establish authority in your field, and generate a steady stream of visitors. Blogging, in particular, is a powerful tool for driving highly targeted traffic to your website.

The reality is, it’s not as black and white as it may seem. There are many factors to consider, whether you’re thinking about making the switch or simply questioning the impact of your current setup.

In this article, we’ll break down the key differences, weigh up the pros and cons, and provide real data to help you make the best decision for your business.

What’s the difference between a subdomain and a subdirectory?

A subdomain (e.g., blog.example.com) is a separate part of a website that functions independently from the main domain. It’s often used for content that serves a different purpose than the main site. For example, an e-commerce business might use a subdomain for its store while keeping its main website focused on content and branding.

A subdirectory (e.g., example.com/blog/) is a section within the main website, keeping all content under the same domain. It’s commonly used for blogs, product categories, and resource pages that align with the main site’s purpose, making navigation and content management more seamless.

When should you use a subdomain?

Since a subdomain acts as a separate entity from the main website, it becomes useful when content, functionality, or tracking needs to be independent.

Use cases and examples

  • Using a different CMS – Some businesses prefer to keep their blog on a separate CMS (e.g., WordPress for blogging while the main site is on Shopify).
  • Tracking & analytics separation – We often work with clients who use HubSpot subdomains for specific tools or marketing campaigns. While we’d love to see them fully transition to a subdirectory on HubSpot, keeping it separate can sometimes make sense for tracking and reporting purposes.
  • Large enterprises with multiple content divisions – News outlets and media brands frequently use subdomains (e.g., news.example.com) to organise different types of content while maintaining brand consistency.
  • E-commerce or separate services – Businesses that run a store on a different platform may use store.example.com to keep transactional content separate from their main informational site.
  • Regional or language-specific sites – International businesses often use au.example.com or fr.example.com to serve content tailored to different countries or languages.

When should you use a subdirectory?

A subdirectory is a good option for small-scale businesses that don’t need extras like a separate CMS or advanced tracking tools. It allows for a simpler, more streamlined website structure, making content easier to manage and navigate.

Use cases and examples

  • Websites with related content under one brand – News sections, blogs, or resource hubs that are directly tied to the main website’s purpose often use a subdirectory to keep everything in one place.
  • E-commerce sites with informational content – Online stores that publish product guides, tutorials, or FAQs may prefer a subdirectory to keep this content alongside their main offerings.
  • Industry or niche blogs – Businesses that want to publish articles, case studies, or updates relevant to their core audience without maintaining a separate domain structure.
  • Websites that do not require a separate platform – If a company manages all its content within one CMS, a subdirectory eliminates the need for additional hosting or system integration.
  • Businesses that prioritise simplicity – Companies that prefer a single, unified website rather than managing multiple domains or subdomains for different content types.

 

Take one of our past marketing clients as an example—their website was split across multiple domains, including a separate blog subdomain. Their blog continued to drive consistent traffic for years without any major ranking issues.

Subdomains and SEO: real evidence

Looking at Semrush data, we found that their main site and blog subdomain have the exact same authority score.

Sub domain:

Main domain:

While authority score isn’t a direct Google ranking factor, it’s a good indicator that the two domains are working together rather than competing.

There is a difference in total backlinks between the two, but thanks to a strong internal linking structure, this doesn’t appear to have a negative impact. Google has stated multiple times that it treats subdomains and subdirectories the same in terms of rankings, so the idea that subdomains are automatically worse for SEO is more of an opinion than a fact.

“Google Web Search is fine with using either subdomains or subdirectories... use what works best for your setup and think about your longer-term plans when picking one or the other.”

Source: Here's a video of John Mueller, a Senior Webmaster Trends Analyst at Google explaining the differences. 

Are subdirectories better for SEO?

There’s some evidence suggesting that subdirectories may rank faster than subdomains, but this is difficult to prove conclusively.

Case study Tweet from Aleyda Solis, the founder of Remotersnet

Most case studies fail to isolate variables like:

  • Increased content output
  • Improved on-page SEO
  • Changes in internal linking
  • External backlink acquisition

Without controlling these factors, the idea that subdirectories are always better for SEO isn’t a black-and-white rule. Instead, the real impact depends on things like website size, content strategy, tracking needs, and site organisation—not just whether a blog sits on a subdomain or subdirectory.

SEO is more than just site structure

Rankings depend on hundreds of factors, and search results can vary case by case depending on the industry. Some websites might benefit more from a subdirectory, while others won’t see any difference at all. Before deciding to migrate a subdomain, it’s important to evaluate other key ranking factors, such as:

  • Content quality & relevance
  • Backlink profile
  • Page speed & UX
  • On-page SEO & internal linking

Should you move to a subdirectory?

If your only reason for switching from a subdomain to a subdirectory is to improve SEO, it’s probably not worth it. There are too many variables at play, and other ranking factors will likely have a far bigger impact on performance. Instead of focusing on site structure alone, businesses should first look at optimising content, improving site experience, and building authority before considering a full migration.

It's about what works best for you

The debate between subdirectories and subdomains has been ongoing for years, but as we’ve seen, there’s no one-size-fits-all answer. Each has its own strengths, and the right choice depends on your website’s structure, technical needs, and long-term goals.

What’s more important is not getting caught up in site structure alone, SEO success is influenced by many factors beyond URL format. Businesses that focus on these elements are far more likely to see long-term gains than those who switch structures hoping for an instant SEO boost.

Instead of viewing this as a technical debate, think about what makes the most sense for your business. Does your blog need to be tightly integrated with the rest of your website? Or does it serve a separate function that requires independence? Answering these questions will help guide your decision in a way that benefits your overall digital strategy.

At the end of the day, both options can work, and what matters most is how well your website is optimised as a whole.