Create a subdomainSet up separate areas under your domain

Published on October 20, 2026

What a subdomain is

A subdomain puts a name part in front of your domain: your-domain.com becomes shop.your-domain.com or blog.your-domain.com. Technically, it is a separate site - with its own directory on the web hosting, its own SSL certificate and its own settings - but it hangs under your existing domain and does not need a second registration.

Two things that are often confused with it should be distinguished:

• A subdirectory such as your-domain.com/shop lives within the same installation and shares its settings.
• A further domain such as your-shop.com is a separate registration with its own costs and its own term.

How many subdomains are available to you depends on the plan: 10 in plan S, 20 in plan M, unlimited from plan L. They are not assigned their own storage - all share the plan's storage.

Create a subdomain in Plesk

1. In Plesk, go to Websites & Domains.
2. Click Add Subdomain.
3. Enter the name - i.e. the part before the dot, such as shop. Letters, digits and hyphens are allowed; you had better avoid special characters and underscores.
4. Select the parent domain if there are several in the plan.
5. Set the document root. Plesk suggests a path based on the name - you can accept it. All that matters is that it differs from the main domain's directory.
6. Save.

After that, the subdomain is usually reachable within a few minutes and shows a placeholder page. Whatever you put into its directory - via FTP or via the file manager - appears under the new address.

If the domain is registered elsewhere

The difference lies with DNS. If your domain runs via our nameservers, Plesk creates the necessary record automatically - you do not have to do anything else.

If, however, your domain only points to the web hosting via an A record while DNS management stays with the previous provider, that provider does not know your new subdomain. Then you add it there yourself:

• Create an A record for the subdomain's name that points to the same IP address as your main domain.
• Alternatively, set a CNAME to the main domain - both work.

Allow for waiting time here too: DNS changes only take effect once the old answer has dropped out of the caches. The details are in the guide Connect a domain.

Do not forget the SSL certificate

A subdomain is not automatically covered by the main domain's certificate. A certificate for your-domain.com does not apply to shop.your-domain.com - visitors would get a security warning there.

So after creating it, issue a separate Let's Encrypt certificate for the subdomain. It is free, included in every plan and takes less than a minute. The prerequisite is that the subdomain is already reachable - the certificate authority checks exactly that.

So the order is: create the subdomain, wait until it responds, issue the certificate, and only then set up content. Anyone who installs an application before the certificate is in place enters the wrong addresses into the database and has to correct them afterwards.

What subdomains are worth it for

A practical advantage in ongoing operation: the PHP version can be set separately per subdomain. An older project that needs a specific version therefore does not block the main site's update.

Subdomain or subdirectory?

For visibility in search engines, the rule of thumb is: content that belongs to the main site in terms of content also belongs in a subdirectory. A blog under your-domain.com/blog contributes to the same domain, while blog.your-domain.com is assessed as a separate site and first has to earn its visibility itself.

Technical reasons, on the other hand, speak for a subdomain:

• It is a separate application with its own database
• It needs a different PHP version
• It should be accessible or backed up separately
• It should not be found at all - test environments, for example, should be kept out of the index via robots.txt and password protection

The last point is often forgotten: a publicly reachable test copy is indexed like any other page - and then competes with the real site for the same content. Protect test environments via directory protection in Plesk, and the problem solves itself.

Frequently asked questions