Fastmail is quite expensive for people who need several mailboxes (not aliases). For anyone with that kind of a need, the cheapest options I've found for emails

Fastmail is quite expensive for people who need several mailboxes (not aliases). For anyone with that kind of a need, the cheapest options I've found for emails are Migadu and mxroute. Both support unlimited domains and mailboxes for a reasonably low fixed price. Go check the prices and compare with Fastmail. You'd be surprised! Migadu doesn't charge for storage space, but its pricing is based on the number of outgoing mails. Mxroute has tiers based on storage space. Migadu has a free tier that you can use forever if you have minimal outgoing email requirements. It's also a good way to check its admin interface. Mxroute has no free tiers or free trials. There's no way to know how it is without paying and signing up. Migadu is based out of Switzerland, with its servers in France (a Nine Eyes country). Mxroute is based out of the U.S. (a Five Eyes country). Neither of these two providers come close to Posteo, Mailbox.org or Mailfence on their privacy statements or stance.