1. Log into your cPanel account.
2. In the
Domains section, click on
Subdomains Icon.
3. Under the
Modify a Subdomain list you can see a list of subdomains.
4. Click the
Remove option under the
Actions tab.
5. You will receive a warning that you are removing a
subdomain.example.com. You will need to click on the
Delete Subdomain button to remove your subdomain permanently.