diff --git a/app/controllers/internal/users_controller.rb b/app/controllers/internal/users_controller.rb
index 948ca2dda..3ebc752de 100644
--- a/app/controllers/internal/users_controller.rb
+++ b/app/controllers/internal/users_controller.rb
@@ -58,7 +58,7 @@ class Internal::UsersController < Internal::ApplicationController
     @user = User.find(params[:id])
     begin
       Moderator::DeleteUser.call(admin: current_user, user: @user, user_params: user_params)
-      flash[:success] = "@" + @user.username + " (email: " + @user.email + ", user_id: " + @user.id.to_s + ") has been fully deleted. If requested, old content may have been ghostified. If this is a GDPR delete, delete them from Mailchimp & Google Analytics."
+      flash[:success] = "@#{@user.username} (email: #{@user.email.presence || 'no email'}, user_id: #{@user.id}) has been fully deleted. If requested, old content may have been ghostified. If this is a GDPR delete, delete them from Mailchimp & Google Analytics."
     rescue StandardError => e
       flash[:danger] = e.message
     end
diff --git a/app/models/user.rb b/app/models/user.rb
index 1a119ce73..02252a586 100644
--- a/app/models/user.rb
+++ b/app/models/user.rb
@@ -463,6 +463,8 @@ class User < ApplicationRecord
   end
 
   def unsubscribe_from_newsletters
+    return if email.blank?
+
     MailchimpBot.new(self).unsubscribe_all_newsletters
   end
 
diff --git a/app/workers/users/delete_worker.rb b/app/workers/users/delete_worker.rb
index 20ab4da67..f36d1b79a 100644
--- a/app/workers/users/delete_worker.rb
+++ b/app/workers/users/delete_worker.rb
@@ -9,7 +9,9 @@ module Users
       return unless user
 
       Users::Delete.call(user)
-      NotifyMailer.account_deleted_email(user).deliver unless admin_delete
+      return if admin_delete || user.email.blank?
+
+      NotifyMailer.account_deleted_email(user).deliver
     rescue StandardError => e
       DatadogStatsClient.count("users.delete", 1, tags: ["action:failed", "user_id:#{user.id}"])
       Rails.logger.error("Error while deleting user: #{e}")
diff --git a/spec/requests/internal/users_spec.rb b/spec/requests/internal/users_spec.rb
index 2928dc4ed..5d55733f8 100644
--- a/spec/requests/internal/users_spec.rb
+++ b/spec/requests/internal/users_spec.rb
@@ -22,7 +22,7 @@ RSpec.describe "internal/users", type: :request do
     end
   end
 
-  describe "GET internal/users/:id/edit" do
+  describe "GET /internal/users/:id/edit" do
     it "redirects from /username/moderate" do
       get "/#{user.username}/moderate"
       expect(response).to redirect_to("/internal/users/#{user.id}")
@@ -39,14 +39,14 @@ RSpec.describe "internal/users", type: :request do
     end
   end
 
-  describe "POST internal/users/:id/banish" do
+  describe "POST /internal/users/:id/banish" do
     it "bans user for spam" do
       post "/internal/users/#{user.id}/banish"
       expect(user.reload.username).to include("spam")
     end
   end
 
-  describe "DELETE internal/users/:id/remove_identity" do
+  describe "DELETE /internal/users/:id/remove_identity" do
     it "removes the given identity" do
       identity = user.identities.first
       delete "/internal/users/#{user.id}/remove_identity", params: { user: { identity_id: identity.id } }
diff --git a/spec/system/internal/admin_deletes_user_spec.rb b/spec/system/internal/admin_deletes_user_spec.rb
new file mode 100644
index 000000000..4facc001c
--- /dev/null
+++ b/spec/system/internal/admin_deletes_user_spec.rb
@@ -0,0 +1,33 @@
+require "rails_helper"
+
+RSpec.describe "Admin deletes user", type: :system do
+  let(:admin) { create(:user, :super_admin) }
+  let(:user) { create(:user) }
+
+  before do
+    sign_in admin
+    visit "/internal/users/#{user.id}/edit"
+  end
+
+  it "enqueues a job for deleting the user" do
+    sidekiq_assert_enqueued_jobs(1, only: Users::DeleteWorker) do
+      click_button "☠️ Fully Delete User & All Activity ☠️"
+    end
+
+    message = "@#{user.username} (email: #{user.email}, user_id: #{user.id}) has been fully deleted."
+    expect(page).to have_content(message)
+  end
+
+  # See: https://github.com/thepracticaldev/tech-private/issues/404
+  it "deletes users when they have no email address" do
+    user.update(email: nil)
+
+    sidekiq_perform_enqueued_jobs do
+      click_button "☠️ Fully Delete User & All Activity ☠️"
+    end
+
+    message = "@#{user.username} (email: no email, user_id: #{user.id}) has been fully deleted."
+    expect(page).to have_content(message)
+    expect(User.find_by(id: user.id)).to be_nil
+  end
+end