4795 shaares
Top contenders:
Mailfence - Belgian, e3.50/mo
Mailbox.org - German, e3/mo; e1/mo plan only allows custom domain for "team accounts" (more than one account? does the first one have to do the e3 plan?)
Posteo - German, no personal domains
Runbox - Norwegian, inexpensive
Soverin: Dutch, € 3.25/mo
Protonmail or Kolab - Swiss, a bit steep; Protonmail e4.00/mo paid annually
Infomaniak: e1.50/mo (..?)
Pobox: US-based, seems like only the expensive account is for custom domains
Msgsafe.io: defunct
Countermail: Swedish, ~$4/mo
Disroot: Dutch, free but requires donation to use custom domain
Spaceship may not be super-private, but it's economical and US-based
Porkbun: Oregon, $24/year but only 20 max addresses
