Depending on your needs, some of the cheaper alternatives focused on privacy and located in Europe are: * Posteo.de (no custom domain support) * Mailbox.org

Depending on your needs, some of the cheaper alternatives focused on privacy and located in Europe are: * Posteo.de (no custom domain support) * Mailbox.org * Runbox.com * Mailfence.com If a service located in the U.S. is not a concern, then mxroute has great options for multiple domains and multiple mailboxes. Services like Fastmail and Hey become quite expensive if you need more than a couple of mailboxes (not aliases). ProtonMail and Tutanota, though privacy focused, can also get expensive for multiple mailboxes. While ProtonMail has some support for IMAP on paid plans, Tutanota does not support it.