diff --git a/app/mailers/user_mailer.rb b/app/mailers/user_mailer.rb
index 8f3a4ab3a..b494e62fb 100644
--- a/app/mailers/user_mailer.rb
+++ b/app/mailers/user_mailer.rb
@@ -63,7 +63,7 @@ class UserMailer < Devise::Mailer
     return if @resource.disabled?
 
     I18n.with_locale(@resource.locale || I18n.default_locale) do
-      mail to: @resource.email, subject: I18n.t('user_mailer.welcome.subject')
+      mail to: @resource.email, subject: I18n.t('user_mailer.welcome.subject', title: Setting.site_title)
     end
   end
 
diff --git a/config/locales/en.yml b/config/locales/en.yml
index d4bf3fd82..3892adb84 100644
--- a/config/locales/en.yml
+++ b/config/locales/en.yml
@@ -1070,7 +1070,7 @@ en:
       full_handle_hint: This is what you would tell your friends so they can message or follow you from another server.
       review_preferences_action: Change preferences
       review_preferences_step: Make sure to set your preferences, such as which emails you'd like to receive, or what privacy level you’d like your posts to default to. If you don’t have motion sickness, you could choose to enable GIF autoplay.
-      subject: Welcome to Mastodon
+      subject: Welcome to %{title}
       tip_federated_timeline: The federated timeline is a firehose view of the wider network. But it only includes people your neighbours are subscribed to, so it's not complete.
       tip_following: You follow your server's admin(s) by default. To find more interesting people, check the local and federated timelines.
       tip_local_timeline: The local timeline is a firehose view of people on %{instance}. These are your immediate neighbours!