app/views contains both controller and mailer directories and becomes cluttered as your application grows. I keep app/views better organized by moving all my *_mailer directories underneath app/views/mailers , which is accomplished with one line of code:

# app/mailers/application_mailer.rb class ApplicationMailer < ActionMailer :: Base default template_path : -> ( e ) { "mailers/ #{ e . class . name . underscore } " } end

Now UsersMailer templates go into app/views/mailers/users_mailer .

It just feels better this way.