Best Practices for Subdomain SEO

Subdomain SEO and Setup for WordPress Sites 

Subdomains are a neat solution for serving different content to different users and streamlining their experience on your site. Apart from the technical side of creating a new subdomain on your website, there’s also the issue of subdomain SEO.

Ensure your domain and subdomain gain the most benefit from your SEO efforts and don’t interfere with each other.

This article will take you through the intricacies and implications of subdomain SEO for your WordPress website.

What is a Subdomain

Your website’s name consists of several domain names. The top-level domain name (TLD) is the element at the end of the website name, like .com .uk or .org. The second-level domain is the name before the TLD. Typically, that’s the name of your website, like yoursite.com. It’s also called the main domain.

In some cases, standardized second-level domains branch out from TLDs, like .co.uk or gov.ua. In that case, your main domain will be considered a third-level domain name.

The subdomain comes before the main domain name. Like blog.yoursite.com, en.yourseite.com, or help.yoursite.com.

In terms of hierarchy and organization, blog.yoursite.com and yoursite.com are two websites hosted on one platform. They’re still connected and hosted on one platform but can have different WordPress templates, analytics tools, and CMS.

You don’t have to pay to register a subdomain like you would for a completely new domain. Typically, registrars allow around a hundred subdomains to be created for a single domain for free.

Subdomain use cases

The typical use of subdomains is to provide different experiences to people on your website. For instance, it’s useful if you want to present one type of visual experience on your main site that shows landing pages and pricing, and another on your blog. 

Only in a few cases are subdomains typically used, though. One is for different language versions if your site has thousands of pages. Another is for separating thematically different sections. For example, if your company does marketing and tech services for B2B clients, you can separate those into two subdomains.

One of the benefits of subdomains is that they can be used for testing purposes. You can create a copy of your website, hide it from search engine indexing, and explore design solutions without jeopardizing your main domain.

The rest, like separating a blog or a store, can just as easily be done with subfolders.

Difference between Subdomains and Subdirectories

With search engine optimization, one stark difference lies between subdirectories and subdomains. Blog.yoursite.com is considered by search engines as a separate website from the main domain, while yoursite.com/blog/ is a part of the same website.

This means that when you do SEO for your main domain, it doesn’t affect your subdomain. Any authority backlinks pointing to your website will improve SEO for the subdirectories of that domain, but won’t do anything for the subdomain.

This makes managing SEO for a website with multiple subdomains trickier to handle because it takes more effort to build website authority for each.

When setting up a subdomain, integrate it into your SEO efforts. Set up analytical tools for it, like GA4 or any rank-tracking tool.

Make sure there’s no duplicate content on the subdomain. Otherwise, it will compete with your main domain in search and might hurt organic traffic. 

If you want to share authority between the two domains, consider cross-linking them. You’ll likely have navigational links from one subdomain to the others, which improves the subdomain’s SEO. You can go further and link between pages on the two domains.

How to Set Up a Subdomain

Once you’ve planned out what content to publish on your new subdomain and picked out a name, here’s how you create one.

Set up a subdomain via a hosting provider

1. Go to your hosting website.
2. Open the hosting dashboard, most commonly, it’s cPanel.
3. Go to Domains.
4. Look for the button called “Create a new domain.” It may be under the Subdomains folder.
5. Type in the name of the subdomain you want to create.
6. Specify the directory where you want the files to be stored. If you choose the option to share the directory, the subdomain will display the same content as the main domain.
7. Submit the changes.

Set up a subdomain via a registrar

Alternatively, you can create a subdomain on your domain registrar’s website.

1. Log in to your registrar’s admin panel.
2. Choose the domain you want to add the subdomain to.
3. Go to DNS records.
4. Click “Add a new record.”
5. Type in the subdomain name.
6. Submit the changes.

It typically takes under an hour for the new subdomain to become functional with both methods.

Install WordPress

After this, install WordPress on your subdomain. If your hosting has an auto-installer, use that and select your new subdomain from the list of options. You can also install WordPress manually by downloading the files and placing them in the subdomain root folder on your hosting.

You can create a WordPress multisite network instead. This means that both the main site and the subdomain will share WordPress installation files.

Find a theme different from the main domain and configure the rest of WordPress.

How to Optimize Subdomains for SEO

Since you’re creating a new website, you’ll have to create the page hierarchy and technical aspects of the website from scratch, which leaves room for a clean slate to optimize for SEO.

Keyword research

Start with keyword research and mapping out potential subdomain subdivisions. Base your category pages and content pages on the keyword clusters you find. It can differ from how the main website is set up, especially if the subdomain covers a different topic.

Website infrastructure

Create an easy-to-follow, crawlable structure in the new subdomain. Don’t overuse subcategories and try to keep the important pages no more than three clicks away from the home page. This both improves UX and ensures Google crawlers can discover your pages.

The URLs for both categories and pages should be informative, meet user intent, and be optimized for a target which you want that page to rank for. 

If you’re taking content from the main domain, add a canonical to the page. A rel= “canonical” in the header of the page shows Google and other search engines that this page is a copy of another. It won’t be flagged as duplicate content, and Google will only show the original page in search results.

Robots.txt

The robots.txt file is separate for each subdomain. Create one that corresponds to your subdomain’s structure and blocks only the parts you do not want to be indexed. If it’s a testing domain you don’t want to be indexed entirely, put this in the file:

User-agent: *

Disallow: /

Sitemap

WordPress should generate a sitemap for all subdomains automatically. It should be visible on this URL: subdomain.yoursite.com/wp-sitemap.xml. If something went wrong and the map either isn’t generated or is generated wrong, generate it with an SEO plugin.

How to Create Content for Subdomains

When your WordPress subdomain is set up, populate it with content. Here’s where you start.

Keyword research

The first step is keyword research tailored to the theme of the subdomain. This might mean looking for informational keywords for a blog, multiple commercial keywords for a store, or keywords in a different language for a language variant of your site.

Combine keywords into groups by similarity and include keywords from one group into the content naturally. It’s okay to break down keywords by small words like prepositions or change the form of the word.

Content production

Create content and optimize your subdomain for SEO by adding corresponding keywords to each page. It’s best to start with content that is more likely to produce results. You can gauge that by the keyword difficulty level of the keywords associated with it.

To streamline content production and create content faster, use a tool like AI Writer by SE Ranking. This tool uses AI to help you improve all stages of the content production process, from ideation to writing the draft. It will also help you include keywords in the text.

Internal linking

Once you have enough content on the subdomain, start linking from your main domain to those pages. Include links naturally across the sites, both as navigational links and inside the content. It will help pass some authority that your main domain has earned to the subdomain.

Link from subdomain pages to the main domain as well. There are tools that find good placements for internal links automatically.

How to Monitor Subdomain SEO Efforts

To make sure your SEO efforts are working, monitor your subdomain’s performance. Here are the steps you need to take.

Set up analytics

Add a new property in Google Search Console and connect Google Analytics to the subdomain, then add it in the SEO tools for tracking.

Once that’s done, track SEO metrics like keyword rankings, traffic, conversions, and engagement on the pages. Keep in mind that it might take some time for Google to recrawl your site and discover new optimizations you’ve made. SEO work will not immediately translate to improved rankings, so there’s always going to be a time lag.

Run SEO audits

While tracking performance and optimizing your site accordingly, run a monthly or quarterly SEO audit. This will spot issues with your subdomain that might disrupt crawling and decrease Core Web Vitals.

Keep WordPress themes and plugins updated to improve performance and avoid security risks from old software.

Excel with Your New Subdomain

Creating a subdomain on your WordPress website can be a great way to test design changes or separate different types of content on your website. Create one in your host’s cPanel, add WordPress on it, and optimize the website structure for SEO.

Work on creating content, optimizing it for the right keywords, and fine-tuning your subdomain SEO strategy based on performance tracking.