While there is much consensus within SEO communities surrounding best practice approaches to our campaigns – a strong focus on well-targeted keywords, high-quality and relevant content, and on-page optimisation, to new a few – there are also several areas where discussion and disagreements still run rampant.
One of the biggest? The debate between subdomains and subdirectories.
To the untrained eye, this might seem like a minuscule difference in site structure that should not impact your ability to rank higher on SERPs. But with the SEO landscape constantly growing more competitive across both common and niche industries, it is essential to know the Google algorithm’s preferences on this, as well as the solution that works best for you.
In this article, the Clearwater team will introduce you to the differences between a subdomain and subdirectory, how they impact the technical aspects of your SEO campaigns, and when you should apply them for the best results.
Subdomain vs Subdirectory: What’s the Difference?
Instead of jumping straight into the debate, it would be prudent first to cover the technical definitions and differences that exist between subdomains and subdirectories.
What is a Subdomain?
Think of a subdomain as a separate website – in fact, they are often referred to as a ‘child’ of your ‘parent’ domain. Put simply, your subdomain will have an association with your existing domain, but not the website attached to it, instead establishing an independent website for users to visit.
Many online publishers opt to use subdomains to host their blogs, eCommerce stores, when they have international websites tailored to wider audiences and to direct traffic to quotation tools. This way, they can avoid over-cluttering their main website, improving users experience, load times, and other crucial metrics for success.
What is a Subdirectory?
A subdirectory keeps everything organised within your web pages, separated into their own different categories and sections. Rather than separate online entities like subdomains, think of subdirectories like subfolders within the larger folders you would use on your computer, only inside your website.
As you can see from the example above, everything sits within the domain and the associated website, acting as just another page on the website.
How Does Website Structure Impact Your SEO Campaign?
Given the explanations provided above, it’s plain to see that the debate around subdomains vs subdirectories is related to the structure of your website and how that structure impacts your broader SEO campaign.
Your website structure will impact:
- User experience: Websites that are easier to navigate and offer a frictionless experience are far more likely to receive longer session times, increased pages per visit and greater conversion rates
- Improved indexation: Structures that are better laid out and make it easier for search engine bots to crawl will, in turn, improve how your pages are indexed.
- Preventing keyword cannibalisation: Your on-site content can cover distinct topics and hold unique keywords to better inform search engines the pages’ desired intention.
There will be scenarios when it is more appropriate to have a subdomain and subdirectory.
As mentioned above, a subdomain will actually be viewed by search engines like Google as completely isolated from your primary domain, given that each will hold unique content and the management of these sites can be performed separately.
If you’re fairly fluent with SEO, you might see the potential issue that arises here. After spending so much time creating keyword-filled and engaging content, as well as a range of quality backlinks delivering valuable authority to your domain, this won’t be considered by Google and other search engines when using a subdomain.
But this isn’t necessarily a bad thing, especially when the subdomain has been created with the intention of separating divisions, markets or businesses using online content. In fact, Google’s John Mueller has previously gone on the record to explain how the search engine is fine with both subdomains and subdirectories.
The best option for your online presence will depend on your specific situation.
When to Use a Subdomain For Your Site Structure?
So, if creating a subdomain means you can’t utilise the authority built from your parent domain, when would there be an appropriate time to use it as your site structure?
Well, there is actually a selection of possible scenarios where a domain can be preferable:
Staging Sites & Technical Applications
Web developers often set up a password-protected subdomain to host a staging site (a copy of your website to test new designs and functions before going live). This is an easy way to make creative and bold new changes to your website without interrupting your existing web pages. Moreover, unless there is a clear link from your primary website or other online sources to your subdomain, search engines will not crawl the staging site.
Developers also often find it far simpler to build a new database or CMS within the subdomain and treat it separately from the wider website, as doing so on a subdirectory can prove challenging, especially with link structure errors. You will also often see popular project management tools, such as ClickUp & Monday.com, using this method. Their commercial website will simply be their brand name followed by the trusty ‘dot com’, but once you purchase and utilise the software, the URL will change to:
Not all your pages need to work their hardest to be found on search engines. Brands and publishers will often select a subdomain over building out their subdirectories to maintain branding purposes, but not clutter their main site.
A common example of this would be for support pages, FAQs and downloadable subject matter. Businesses partnering with other organisations on various programs or joint ventures can also adopt this method. To maintain branding without overcrowding their subdirectory (as well as preventing an external business from holding any real estate on their main domain), a subdomain can be the perfect solution.
Given the ever-growing ease and popularity of selling products online, it is not unheard of for modern brands providing traditional products or services to also establish an eCommerce store. It’s quite lucrative; marketing associated goods to establish a whole new revenue stream boasting a high-profit margin.
Unfortunately, including all these individual categories and product pages can leave your main site overly dense and hard to navigate. As a solution, a subdomain can provide a separate location to house your online store.
SEO Campaign Support
Plenty of SEO measures are still shrouded in mystery and are heavily debated amongst specialists in the industry. Many proponents, however, believe that Google ranks a subdomain section more favourably when not influenced by the main site (and the other way round).
As a result, this has become a widespread practice among publishers who wish to isolate a section of content completely different to that on their main website, such as when expanding offerings or operating in different regions (nationally or internationally).
Whether this has a definite effect on boosting your rankings will require more data and analysis. In the meantime, publishers may recognise associated benefits, such as a leaner main domain and subdomain, each boasting faster load speeds and offering a far easier management schedule that multiple teams can share.
How are Subdirectories Beneficial as Your Website Structure?
Despite the range of benefits and scenarios where a subdomain may prove useful, it is important to recognise the place for subdirectories, especially when looking to get the most out of your SEO campaigns.
As alluded to above, you need to consider the main ranking factors influencing Google’s algorithm – content, keywords and links.
Through the content you introduce on your web pages, the keywords you filter through them and in your metadata, and the quality & quantity of the links you attract, you will gradually build authority within your industry in the eyes of search engines. While there are myriad other factors at play (on-page optimisation, mobile friendliness, load speeds and so on), this authority will help determine the success of your domains ranking in SERPs.
Now, suppose you split all of your content and the links you have spent months or years acquiring between your main domain and subdomain, rather than consolidating them under one domain through a subdirectory. In that case, you will also essentially split your potential authority between them, impacting how high your site(s) rank for targeted keywords in SERPs. In fact, should some of your content and keywords exist on both sites, you might even find some cannibalisation and duplication occurring, further hurting your SEO efforts.
This is why many brands and blogs have noticed a rise in their wider organic visibility and subsequent traffic generated by search engines after migrating all associated subdomains into subfolders within a primary domain. The newly created subdirectory inherits all the accumulated authority to better compete against others in the industry, rather than a single brand competing with itself.
Are There Challenges to Consider with Subdirectories?
Now we have discussed the potential subdirectories claim greater authority in the eyes of search engines, it might be tempting to forgo the benefits of subdomains mentioned earlier.
Don’t be so quick to make up your mind, though. Subdirectories aren’t a perfect science.
As you build out your online presence through subdirectories, you will likely encounter a range of limitations that may make you search for compromises or switch to subdomains.
Examples of these potential issues include:
- Difficulties creating international pages within your subfolders, such as ‘domain.com/us’ or ‘domain.com/au’
- Introducing features written in other coding languages, such as quote and booking forms, meaning they cannot reside on the same server as the main website
- A preference from developers and publishers to avoid hosting a blog on the same server as an eCommerce store
You may have already run into these roadblocks on your development journey, such Shopify users finding the platform insists on international stores having subdomains instead of subdirectories (i.e., au.domain.com).
Which Should You Choose: Subdirectory or Subdomain
With all the information explored above, it is commonly understood that a subdirectory is the preferred option over subdomains in terms of your SEO campaign, especially without any technical or legal restrictions across the countries you are operating in. By choosing to work with a subdirectory, you can:
- Introduce a greater amount of unique content without fear of duplication
- Avoid competing keywords in your main domain and subdomain
- Attract and accumulate links in one centralised location to build your authority with search engines
- Introduce tailored internal linking opportunities to create connections between sections, extend user pathways and improve their experience
Find the Right Choice for Your Business Needs
Again, it is worth reiterating that this decision shouldn’t be made off generalities. Instead, take close consideration of your individual circumstances, such as when you are looking to expand the material you offer online, like quote forms and a support hub. By placing these branded pieces in a location outside of your main domain won’t adversely impact its SEO performance.
Before deciding to influence the amount of organic sent to your target pages, be sure to fully understand the different applications of subdomains and subdirectories, and how they impact your SEO campaign.
For more information from specialists in the field, reach out to one of our SEO technicians at Clearwater today. We would be happy to discuss your unique needs and develop a tailored recommendation to achieve the best results for your digital strategy.