Adding a Domain in cPanel: Addon, Alias, or Subdomain

When you add a domain in cPanel, you are picking one of three things: an addon domain, an alias (parked) domain, or a subdomain. The cPanel Create a New Domain page does not name them, but the choice determines how the domain serves content and how you manage it later. This guide explains the differences, when to use each, and how the form maps to your decision.

01. The Three Types of Domains

Older versions of cPanel had three separate icons for Addon Domains, Aliases, and Subdomains. The Jupiter theme combined them into a single Create a New Domain page where the type is determined by what you enter and whether you share the document root. The underlying concepts have not changed, just where you click.

Here is what each one does:

• Addon Domain - a completely separate website on a different domain name. Different content, different files, its own email accounts. From a visitor's perspective, an addon domain is indistinguishable from a main domain.
• Alias Domain (also called Parked Domain) - an additional name that points at the same content as one of your existing sites. Visitors who type either name see identical pages. See also What is a Domain Name Pointer or Parked Domain? for background.
• Subdomain - a prefix on a domain you already host, such as blog.yourdomain.com or shop.yourdomain.com. It has its own folder and can host different content from the parent domain.

02. Addon Domain: A Separate Website

Pick this when you have a brand new domain name and you want it to host a different website than your main domain. Different homepage, different pages, optionally different email accounts.

Example: Your main domain is widgetshop.com. You buy gadgetstore.com for a second business. You want each domain to have its own homepage, its own content, and its own pricing pages.

What cPanel creates:

• A new folder under your account, typically /home/youruser/public_html/gadgetstore.com
• DNS records pointing the new domain to your account
• The ability to create email accounts on the new domain

What you do in cPanel:

1. Domain field - enter the new domain name (e.g., gadgetstore.com)
2. Share document root - leave UNCHECKED
3. Document root field - leave the suggested path, or customize the folder name
4. Click Submit

03. Alias (Parked) Domain: An Alternate Name

Pick this when you want a second domain to display the exact same content as your existing site. The two domains will serve identical pages because they share the same folder on the server.

Example: Your main domain is widgetshop.com. You also bought widgetshop.net and widget-shop.com to protect your brand and catch typos. You want all three names to land on the same pages.

What cPanel creates:

• DNS records pointing the alias to your account
• An Apache configuration that serves the alias from your main domain's folder
• No new folder is created, that is the point - it shares the existing one

What you do in cPanel:

1. Domain field - enter the alias name (e.g., widgetshop.net)
2. Share document root - CHECK this box
3. Click Submit

04. Subdomain: A Section of an Existing Site

Pick this when you want a different section of one of your existing domains, accessed by a name like shop.yourdomain.com, blog.yourdomain.com, or staging.yourdomain.com.

Example: Your main domain is widgetshop.com. You want a blog at blog.widgetshop.com that has its own WordPress installation independent of the main site.

What cPanel creates:

• A new folder under your account, typically /home/youruser/public_html/blog or /home/youruser/public_html/blog.widgetshop.com
• A DNS record adding the subdomain to your zone
• An Apache configuration serving the subdomain from the new folder

What you do in cPanel:

1. Domain field - enter the full subdomain name including the dot (e.g., blog.widgetshop.com, NOT just blog)
2. Share document root - leave UNCHECKED
3. Document root field - leave the suggested path
4. Click Submit

05. How the cPanel Form Maps to Your Choice

The Create a New Domain page is the same form for all three types. The combination of what you enter in the Domain field and whether you check "Share document root" determines what cPanel creates:

06. After You Add the Domain

Once cPanel reports success, some things happen automatically and some you may need to handle.

Automatic

• DNS zone update - cPanel adds the domain to its zone file and notifies the nameservers. Addon domains and subdomains start resolving within a few minutes if the registrar is already pointing to our nameservers.
• SSL certificate - AutoSSL runs on a schedule and will issue a free Let's Encrypt certificate for the new domain, typically within an hour. You can also trigger it manually from cPanel > SSL/TLS Status.
• Apache configuration - the new domain or subdomain becomes active on the web server.

Manual (if needed)

• Upload content - addon domains and subdomains with their own document root start with an empty folder. Upload your site files via the File Manager or FTP.
• Create email accounts - if you want email on the new domain, set it up via cPanel > Email Accounts. See our email setup guide.
• Install a CMS - if the new domain needs WordPress or another platform, install it into the new document root rather than the main domain's folder.
• Check nameservers - if the domain is not resolving after an hour, confirm the registrar has it set to ns1.ultranameservers.com, ns2.ultranameservers.com, and ns3.ultranameservers.com.

07. Common Mistakes to Avoid

Sharing the document root by accident

For a long time the cPanel form defaulted to having "Share document root" checked, which surprised people. If you added a new domain expecting a separate site and it shows the same content as your main site, this is likely why. The fix is to remove the domain from cPanel > Domains and re-add it with the box unchecked. The new addon will have an empty document root, so you will need to upload content.

Entering just "blog" instead of "blog.yourdomain.com"

The Domain field requires the full hostname including the parent domain. If you enter just blog, cPanel will reject it because it is not a valid domain name. Enter blog.yourdomain.com (the full name with the dot) to create a subdomain.

Adding a domain before transferring nameservers

Adding a domain in cPanel does not register the domain or change its nameservers. If the domain still points at its old host or its registrar's default nameservers, adding it to cPanel will not make the site load. The nameservers at the registrar must point to ns1.ultranameservers.com, ns2.ultranameservers.com, and ns3.ultranameservers.com for the domain to resolve to our servers.

Treating an alias as an addon

If you intend two separate websites, do not use an alias. An alias permanently ties the new domain to the main domain's folder. The cPanel warning "This setting is permanent" means you cannot later separate them without removing and re-adding the domain.

08. Troubleshooting

"Domain already exists" error

The domain is already added to your account, another account on the same server, or a different cPanel server in our fleet. Check cPanel > Domains to confirm. If it is on another account, that account holder needs to remove it before you can add it. Open a support ticket if you cannot identify where the conflict is.

The new domain shows my main domain's content

"Share document root" was checked when you created the domain, so it is acting as an alias. To fix this, remove the domain from cPanel > Domains and re-add it with the box unchecked. Be aware that removing the domain does not delete the files in the document root.

The new domain shows a 404 or blank page

The document root folder exists but has no content yet. Upload an index.html or index.php file via File Manager or FTP, or install a CMS like WordPress into the folder.

The new domain works but has no SSL

AutoSSL has not yet issued a certificate for the new domain. Wait up to an hour, or trigger it manually from cPanel > SSL/TLS Status by clicking Run AutoSSL. If AutoSSL fails, confirm that DNS is resolving correctly for the domain first.

The cPanel form will not accept my domain name

The Domain field validates against standard domain syntax. Common rejections: spaces, underscores in the wrong place, missing TLD (you must include .com, .net, etc.), or trailing dots. Wildcard subdomains (*.yourdomain.com) are accepted but only as subdomains, not as addon domains.

Quick Recap: The Decision Tree

If you only remember a few things from this guide:

1. Different content on a different domain - addon domain, share document root UNCHECKED
2. Same content under a different name - alias / parked, share document root CHECKED
3. Section of your existing site - subdomain, full name with dot, share document root UNCHECKED
4. Check nameservers at the registrar before adding the domain to cPanel
5. If you picked wrong, remove and re-add. Alias is permanent, and a new addon's folder will be empty.

Last updated May 2026 · Browse all cPanel articles