When you buy a domain, the name you buy– such as “example.com” or “example.co.uk”– is called the “root domain”. Your domain registrar will also allow you to use subdomains, such as “www.example.com” or “blog.example.co.uk”.
Why does Substack require "www" in my newsletter URL?
Some domain registrars, including GoDaddy and Google Domains, only allow CNAME records to point from a subdomain and not from a root domain (this is sometimes called “CNAME flattening”). For example, on Godaddy, you won’t be able to use example.com for your Substack publication, but you will be able to use www.example.com.
If you've registered your domain with one of these registrars, we require a subdomain for your Substack.
Formats that work:
Format that won't work:
Is there a workaround?
After setting up a CNAME for your newsletter, the next step is to set up a 301 redirect that basically forwards the non-www version of your custom domain to the www URL.
example.com → www.example.com
Below is the screen you should see when setting up a 301 on GoDaddy:
Interested in using your custom domain for your Substack publication? Learn more here on how to get started!