4 files changed, 17 insertions, 4 deletions
diff --git a/actionmailer/CHANGELOG.md b/actionmailer/CHANGELOG.md
index 787dc46f00..c5e51b6fbd 100644
--- a/actionmailer/CHANGELOG.md
+++ b/actionmailer/CHANGELOG.md
@@ -29,4 +29,11 @@
 
     *Rafael Mendonça França*
 
+*   Add `_mailer` suffix to mailers created via generator, following the same
+naming convention used in controllers and jobs.
+
+    Closes #18074.
+
+    *Carlos Souza*
+
 Please check [4-2-stable](https://github.com/rails/rails/blob/4-2-stable/actionmailer/CHANGELOG.md) for previous changes.
diff --git a/actionmailer/lib/rails/generators/mailer/USAGE b/actionmailer/lib/rails/generators/mailer/USAGE
index 323bb8a87f..d9d9d064d8 100644
--- a/actionmailer/lib/rails/generators/mailer/USAGE
+++ b/actionmailer/lib/rails/generators/mailer/USAGE
@@ -11,7 +11,7 @@ Example:
     rails generate mailer Notifications signup forgot_password invoice
 
     creates a Notifications mailer class, views, and test:
-        Mailer:     app/mailers/notifications.rb
+        Mailer:     app/mailers/notifications_mailer.rb
         Views:      app/views/notifications/signup.text.erb [...]
         Test:       test/mailers/notifications_test.rb
 
diff --git a/actionmailer/lib/rails/generators/mailer/mailer_generator.rb b/actionmailer/lib/rails/generators/mailer/mailer_generator.rb
index 83f8a67da7..3ec7d3d896 100644
--- a/actionmailer/lib/rails/generators/mailer/mailer_generator.rb
+++ b/actionmailer/lib/rails/generators/mailer/mailer_generator.rb
@@ -4,16 +4,22 @@ module Rails
       source_root File.expand_path("../templates", __FILE__)
 
       argument :actions, type: :array, default: [], banner: "method method"
-      check_class_collision
+
+      check_class_collision suffix: "Mailer"
 
       def create_mailer_file
-        template "mailer.rb", File.join('app/mailers', class_path, "#{file_name}.rb")
+        template "mailer.rb", File.join('app/mailers', class_path, "#{file_name}_mailer.rb")
         if self.behavior == :invoke
           template "application_mailer.rb", 'app/mailers/application_mailer.rb'
         end
       end
 
       hook_for :template_engine, :test_framework
+
+      protected
+        def file_name
+          @_file_name ||= super.gsub(/\_mailer/i, '')
+        end
     end
   end
 end
diff --git a/actionmailer/lib/rails/generators/mailer/templates/mailer.rb b/actionmailer/lib/rails/generators/mailer/templates/mailer.rb
index bce64a5e6e..b9be70a2f0 100644
--- a/actionmailer/lib/rails/generators/mailer/templates/mailer.rb
+++ b/actionmailer/lib/rails/generators/mailer/templates/mailer.rb
@@ -1,5 +1,5 @@
 <% module_namespacing do -%>
-class <%= class_name %> < ApplicationMailer
+class <%= class_name %>Mailer < ApplicationMailer
 <% actions.each do |action| -%>
 
   # Subject can be set in your I18n file at config/locales/en.yml