mihha I guess that you have missed it, but it is there https://docs.acymailing.com/main-pages/users/import
mihha You could use Universal filter https://docs.acymailing.com/addons/all-cms-add-ons/universal-filter With it, you can use Mass action to connect to the external DB and import users https://docs.acymailing.com/addons/all-cms-add-ons/universal-filter#users-based-on-an-advanced-sql-query
