Why can't I delete the original netlify domain?

Hi all,

I have added a custom domain to my website and I made it the ‘Primary domain’ of my website, which is live.

However, in the Domain management - Domains settings, I am unable to delete the originally assigned Netlify free domain, which is set as the ‘Default subdomain’.

Why can’t I delete this Netlify subdomain? The issue I have with this is that search engines are picking this up and indexing it over my Primary domain and it is confusing to visitors having to deal with two domains when I brought over my custom domain? How can this be fixed and the Netlify domain either be deleted altogether or fully deactivated so that search engines don’t index it?

Thanks in advance

Netlify automatically adds canonical headers to Netlify subdomain: URL Canonicalization and the Canonical Tag | Google Search Central  |  Documentation  |  Google Developers, so if the issue still happens, it’s a problem with the Search Engines not respecting that, not a Netlify issue.

Regardless, you can use Netlify Redirects: Redirects and rewrites | Netlify Docs to redirect the subdomain to your custom domain.