A private Substack publication is a secret publication you can host alone or invite others to join. Once you enable this feature, your Substack will be blocked from the public, but any current readers (free subscribers and/or paying subscribers) will still have access to the private publication.
You can decide not to invite anyone to your private publication or invite others to join by email. You can also give access to your paying subscribers to invite up to 10 friends.
To turn this on, navigate to your Settings page then check the box next to “Invite-only mode”.