New Domain or Subdomain? Which is Better for SEO?

Graphic of a man looking at a computer screen with two different website designs labeled "new site" and "subdomain", trying to decide which is better for SEO

You finally made it! Your business website finally gets tons of organic traffic and converts well. You have put years of effort into your content, design, structure, SEO, UX, etc. Your visitors love your content, and you get good feedback from your users.

Now your business is successful, and it’s time to scale. You and/or your partners come up with a brilliant new expansion idea. The plan is created, and you’re almost ready to show your new idea to the world, but something is missing, isn’t it? It needs a website!

We know it’s exciting at this point to dive into the design of a new brand and website for your new offering or target audience but take a moment to consider that from an SEO point of view, you’d be starting over from scratch. Why not ride the tailwinds of your already successful website instead?

You can still do all the fun stuff: creating a new logo, design, messaging, etc. – essentially, a whole new website. But consider hosting this new site on a subdomain of your existing website. 

We have a case study from our very own website that speaks to the SEO power of the subdomain approach. 

But first, let’s go over what we mean by “subdomain.” 

What is a Subdomain?

The term “subdomain” refers to the beginning part of a URL, for example:

In the first example, the “www” is the subdomain. In the second example, “otherthing” is the subdomain. Since “www” is such a common subdomain, it often doesn’t get referred to as such. Usually, when people talk about a website subdomain, they are referring to using something other than “www” in front of the website URL. 

How does a subdomain work? 

Using DNS, subdomains can be pointed to an entirely different CMS (Content Management System) than the main site. They can even be pointed to separate servers as well.

Because of this, Google and other search engines treat subdomains as somewhat of a different site; however, a subdomain makes it apparent that both the main site and the subdomain website are tied to the same entity. So, creating a subdomain is like a half-new site, half-not-new site (in the eyes of the search engines).

Subdomain vs. Subdirectory (or Subfolder)

You may also hear people refer to “subdirectories” or “subfolders.” Both of these terms mean the same thing, which is the middle part of a URL. For example:

Subdirectories organize content on a website and are good for SEO as they help the search engine bots understand the structure and organization of your content.

Are Subdomains Good or Bad for SEO?

You’ll find mixed opinions on this, but the real answer is the same as the answer to many other SEO questions, which is… “It depends.” Let’s get into some of the factors that this decision should depend on: 

Use Subdirectories If…

First, here are some situations where you should not consider hosting your content on anything other than a new URL or subdirectory of your existing site:

  • Your target audience for the new offering is the same as the existing offerings
  • You are adding a new content section to your site, such as a blog or resource library

In those situations, just add a new page or subdirectory (a.k.a. subfolder) to your existing site. When separate audience messaging or different branding isn’t required, then it’s best to simply expand your existing site.

Use Subdomains If…

Now here are some situations where you really should consider hosting the new site on a subdomain instead of a separate domain:

  • You need to market to a new and different target audience than the existing site
  • You are launching a new product or service that will have its own distinct brand
  • Your new website will be for a new collaboration (e.g., joint venture) that will be co-branded with another company 
  • You’re opening an office in another region or country, and you need a local traffic acquisition channel and/or need to have multiple language versions of your site
  • Your existing website was never an online store, but now you have products to ship to your customers and need to launch an eCommerce platform 
  • You’re running PPC or other ad campaigns that require landing pages that, if added to your current site, would make it a little too messy
  • You need a separate domain for marketing materials (business cards, email addresses, etc.) (Go ahead and buy it – but redirect it to the subdomain URL)
  • You already bought a domain for it but never used it (again, just redirect it to the subdomain)

Use Separate Domains If…

Lastly, here are some scenarios where it might make more sense to use a separate domain:

  • You already created a separate website that receives a decent amount of Google rankings and SEO traffic
  • You are merging two existing brands with two existing sites/domains that generate SEO traffic

As you can see, the main difference is whether or not you already have another domain (or domains) actively receiving SEO traffic. In those cases, it’s best to consult with an SEO professional to create a custom strategy for preserving and enhancing the SEO traffic of the various domains.

What are the benefits of using a subdomain versus launching a new domain?

The Subdomain Will Benefit From the Main Domain’s SEO Authority

First of all, since a subdomain uses your existing domain (e.g.,, your existing domain’s history and authority (a.k.a. “domain rank”) will serve as a foundation for the new site’s SEO “juice” (traction). As opposed to starting from zero SEO authority, the subdomain will benefit from the authority of the main domain. The new site will still need to build its own traction with technical SEO optimizations, content, and keywords, but at least the domain authority will not be starting from zero. The subdomain won’t be assigned all of the authority of the main domain, but it will certainly be assigned some authority just from the fact that it’s tied to your existing domain.

So you will still need to develop an SEO strategy for the new site. You’ll need to ensure that it’s technically optimized, has specific high-intent keywords assigned to your new pages, and is regularly updated with high-quality SEO-optimized content that will help the audience understand the topic and add some “fuel” to your new “engine.” But at least you’ll get a head start in the domain authority-building part of your new site’s SEO efforts.

The Main Domain Will Also Benefit From the Subdomain’s SEO Authority!

In addition to the main domain immediately giving the subdomain an SEO authority boost at launch, any new inbound links that the main site receives in the future will also have an influence on the new subdomain – AND vice-versa! As your marketing efforts earn you new backlinks for your subdomain, that additional authority will also benefit the main site. Yes, it works both ways!

The New Brand Will Benefit From the Existing Brand’s Trustworthiness

Your new offering will automatically gain a certain level of trust, as users will see that this new site is affiliated with your widely known existing brand. You can further optimize for this effect by offering an additional menu bar at the top of your site that presents a tabbed layout similar to a web browser. This immediately demonstrates to the user that you own both brands. We did this with the Pam Ann and Stealth sites, as you can see below.

Streamlined Maintenance & Management = Cost Savings!

If you will be using WordPress, which we prefer for SEO, you can take advantage of a WordPress Multisite installation. This can greatly streamline your content management, user management, and technical website maintenance efforts – thereby saving you money!

Even if you don’t utilize Multisite, there are still savings that can be realized for hosting and other services that are priced on a per-domain basis. 

Conclusion: In Most Cases, a Subdomain is Better for SEO

In conclusion, the decision between choosing a new domain or a subdomain hinges heavily on your business goals and existing digital assets. But hopefully, we’ve convinced you by now that in most situations, the subdomain option will offer more benefits (SEO and otherwise) than launching a new site on a separate domain.

Our own case study vividly illustrates the power and potential of leveraging an established domain’s authority by opting for a subdomain. 

If you are on the brink of expansion or diversification, consider a subdomain over a new domain, as it can offer a multitude of benefits, from financial savings to SEO advantages. It’s a strategy that merges the strength of an established online presence with the promise of new initiatives, ensuring both are set on a path to digital success.

A Few Final Tips Before You Go…

Search Console

Don’t forget to verify your subdomain through Search Console separately so that you can easily monitor the keyword rankings for the subdomain separately from the main domain. We always recommend setting up a Search Console domain property, but in addition to that, you’ll want to create two URL prefix properties as well: One for the main site and one for the subdomain. 

Google Analytics

You’ll also want to monitor the Google Analytics traffic separately – although we do recommend sharing a single GA4 property across both the main site and subdomain so that you also have the option of seeing everything in one place and seamlessly tracking user behavior across the sites. Monitoring performance separately while sharing a single GA4 property can be achieved by creating custom Google Analytics 4 reports using Looker Studio.

Let Us Help You!

Lastly, and most importantly, reach out to us before you start! We can help you create an SEO “blueprint” for your new site, regardless of whether it’s on a subdomain or a new domain. 

Pam Aungst Cronin
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