The WordPress Restrict Email Domains plugin lets you limit/restrict user registration on your WordPress/ BuddyPress site by email domains. You can limit the registration by specific emails or domains or just the domain extensions (like .edu/.com)

You can limit user registration by email domains for:

• WordPress
• WordPress Multisite
• BuddyPress
• WooCommerce
• Paid Memberships Pro
• WP-Members
• UsersWP
• Ultimate Member

Allows you to limit new user registrations by:

• Domain names (e.g example.com)
• Extensions (e.g. .edu, will only allow emails having .edu domain)
• Email addresses (e.g [email protected], [email protected])