diff --git a/app/mailers/admin_mailer.rb b/app/mailers/admin_mailer.rb
index bc6d87ae6..5baf9b38a 100644
--- a/app/mailers/admin_mailer.rb
+++ b/app/mailers/admin_mailer.rb
@@ -6,45 +6,52 @@ class AdminMailer < ApplicationMailer
   helper :accounts
   helper :languages
 
-  def new_report(recipient, report)
-    @report   = report
-    @me       = recipient
-    @instance = Rails.configuration.x.local_domain
+  before_action :process_params
+  before_action :set_instance
+
+  default to: -> { @me.user_email }
+
+  def new_report(report)
+    @report = report
 
     locale_for_account(@me) do
-      mail to: @me.user_email, subject: I18n.t('admin_mailer.new_report.subject', instance: @instance, id: @report.id)
+      mail subject: default_i18n_subject(instance: @instance, id: @report.id)
     end
   end
 
-  def new_appeal(recipient, appeal)
-    @appeal   = appeal
-    @me       = recipient
-    @instance = Rails.configuration.x.local_domain
+  def new_appeal(appeal)
+    @appeal = appeal
 
     locale_for_account(@me) do
-      mail to: @me.user_email, subject: I18n.t('admin_mailer.new_appeal.subject', instance: @instance, username: @appeal.account.username)
+      mail subject: default_i18n_subject(instance: @instance, username: @appeal.account.username)
     end
   end
 
-  def new_pending_account(recipient, user)
-    @account  = user.account
-    @me       = recipient
-    @instance = Rails.configuration.x.local_domain
+  def new_pending_account(user)
+    @account = user.account
 
     locale_for_account(@me) do
-      mail to: @me.user_email, subject: I18n.t('admin_mailer.new_pending_account.subject', instance: @instance, username: @account.username)
+      mail subject: default_i18n_subject(instance: @instance, username: @account.username)
     end
   end
 
-  def new_trends(recipient, links, tags, statuses)
+  def new_trends(links, tags, statuses)
     @links                  = links
     @tags                   = tags
     @statuses               = statuses
-    @me                     = recipient
-    @instance               = Rails.configuration.x.local_domain
 
     locale_for_account(@me) do
-      mail to: @me.user_email, subject: I18n.t('admin_mailer.new_trends.subject', instance: @instance)
+      mail subject: default_i18n_subject(instance: @instance)
     end
   end
+
+  private
+
+  def process_params
+    @me = params[:recipient]
+  end
+
+  def set_instance
+    @instance = Rails.configuration.x.local_domain
+  end
 end
diff --git a/app/models/trends.rb b/app/models/trends.rb
index d07d62b71..7ca51e0b3 100644
--- a/app/models/trends.rb
+++ b/app/models/trends.rb
@@ -35,7 +35,7 @@ module Trends
     return if links_requiring_review.empty? && tags_requiring_review.empty? && statuses_requiring_review.empty?
 
     User.those_who_can(:manage_taxonomies).includes(:account).find_each do |user|
-      AdminMailer.new_trends(user.account, links_requiring_review, tags_requiring_review, statuses_requiring_review).deliver_later! if user.allows_trends_review_emails?
+      AdminMailer.with(recipient: user.account).new_trends(links_requiring_review, tags_requiring_review, statuses_requiring_review).deliver_later! if user.allows_trends_review_emails?
     end
   end
 
diff --git a/app/models/user.rb b/app/models/user.rb
index 5ee14bbda..fa445af81 100644
--- a/app/models/user.rb
+++ b/app/models/user.rb
@@ -475,7 +475,7 @@ class User < ApplicationRecord
     User.those_who_can(:manage_users).includes(:account).find_each do |u|
       next unless u.allows_pending_account_emails?
 
-      AdminMailer.new_pending_account(u.account, self).deliver_later
+      AdminMailer.with(recipient: u.account).new_pending_account(self).deliver_later
     end
   end
 
diff --git a/app/services/appeal_service.rb b/app/services/appeal_service.rb
index 399a053d6..ef052e354 100644
--- a/app/services/appeal_service.rb
+++ b/app/services/appeal_service.rb
@@ -23,7 +23,7 @@ class AppealService < BaseService
 
   def notify_staff!
     User.those_who_can(:manage_appeals).includes(:account).each do |u|
-      AdminMailer.new_appeal(u.account, @appeal).deliver_later if u.allows_appeal_emails?
+      AdminMailer.with(recipient: u.account).new_appeal(@appeal).deliver_later if u.allows_appeal_emails?
     end
   end
 end
diff --git a/app/services/report_service.rb b/app/services/report_service.rb
index 3444e1dfa..39ebd5cd8 100644
--- a/app/services/report_service.rb
+++ b/app/services/report_service.rb
@@ -40,7 +40,7 @@ class ReportService < BaseService
 
     User.those_who_can(:manage_reports).includes(:account).each do |u|
       LocalNotificationWorker.perform_async(u.account_id, @report.id, 'Report', 'admin.report')
-      AdminMailer.new_report(u.account, @report).deliver_later if u.allows_report_emails?
+      AdminMailer.with(recipient: u.account).new_report(@report).deliver_later if u.allows_report_emails?
     end
   end
 
diff --git a/config/i18n-tasks.yml b/config/i18n-tasks.yml
index 035a0e999..cb00a62d5 100644
--- a/config/i18n-tasks.yml
+++ b/config/i18n-tasks.yml
@@ -63,6 +63,7 @@ ignore_unused:
   - 'admin_mailer.new_appeal.actions.*'
   - 'statuses.attached.*'
   - 'move_handler.carry_{mutes,blocks}_over_text'
+  - 'admin_mailer.*.subject'
   - 'notification_mailer.*'
   - 'imports.overwrite_preambles.{following,blocking,muting,domain_blocking,bookmarks}_html'
   - 'imports.preambles.{following,blocking,muting,domain_blocking,bookmarks}_html'
diff --git a/spec/controllers/api/v1/reports_controller_spec.rb b/spec/controllers/api/v1/reports_controller_spec.rb
index 01b7e4a71..f923ff079 100644
--- a/spec/controllers/api/v1/reports_controller_spec.rb
+++ b/spec/controllers/api/v1/reports_controller_spec.rb
@@ -23,8 +23,6 @@ RSpec.describe Api::V1::ReportsController do
     let(:rule_ids) { nil }
 
     before do
-      allow(AdminMailer).to receive(:new_report)
-        .and_return(instance_double(ActionMailer::MessageDelivery, deliver_later: nil))
       post :create, params: { status_ids: [status.id], account_id: target_account.id, comment: 'reasons', category: category, rule_ids: rule_ids, forward: forward }
     end
 
@@ -41,7 +39,7 @@ RSpec.describe Api::V1::ReportsController do
     end
 
     it 'sends e-mails to admins' do
-      expect(AdminMailer).to have_received(:new_report).with(admin.account, Report)
+      expect(ActionMailer::Base.deliveries.first.to).to eq([admin.email])
     end
 
     context 'when a status does not belong to the reported account' do
diff --git a/spec/controllers/disputes/appeals_controller_spec.rb b/spec/controllers/disputes/appeals_controller_spec.rb
index a0f9c7b91..c8444a2a9 100644
--- a/spec/controllers/disputes/appeals_controller_spec.rb
+++ b/spec/controllers/disputes/appeals_controller_spec.rb
@@ -14,13 +14,11 @@ RSpec.describe Disputes::AppealsController do
     let(:strike) { Fabricate(:account_warning, target_account: current_user.account) }
 
     before do
-      allow(AdminMailer).to receive(:new_appeal)
-        .and_return(instance_double(ActionMailer::MessageDelivery, deliver_later: nil))
       post :create, params: { strike_id: strike.id, appeal: { text: 'Foo' } }
     end
 
     it 'notifies staff about new appeal' do
-      expect(AdminMailer).to have_received(:new_appeal).with(admin.account, Appeal.last)
+      expect(ActionMailer::Base.deliveries.first.to).to eq([admin.email])
     end
 
     it 'redirects back to the strike page' do
diff --git a/spec/mailers/admin_mailer_spec.rb b/spec/mailers/admin_mailer_spec.rb
index 8e2eec40f..9123804a4 100644
--- a/spec/mailers/admin_mailer_spec.rb
+++ b/spec/mailers/admin_mailer_spec.rb
@@ -7,7 +7,7 @@ RSpec.describe AdminMailer do
     let(:sender)    { Fabricate(:account, username: 'John') }
     let(:recipient) { Fabricate(:account, username: 'Mike') }
     let(:report)    { Fabricate(:report, account: sender, target_account: recipient) }
-    let(:mail)      { described_class.new_report(recipient, report) }
+    let(:mail)      { described_class.with(recipient: recipient).new_report(report) }
 
     before do
       recipient.user.update(locale: :en)
@@ -27,7 +27,7 @@ RSpec.describe AdminMailer do
   describe '.new_appeal' do
     let(:appeal) { Fabricate(:appeal) }
     let(:recipient) { Fabricate(:account, username: 'Kurt') }
-    let(:mail)      { described_class.new_appeal(recipient, appeal) }
+    let(:mail)      { described_class.with(recipient: recipient).new_appeal(appeal) }
 
     before do
       recipient.user.update(locale: :en)
@@ -47,7 +47,7 @@ RSpec.describe AdminMailer do
   describe '.new_pending_account' do
     let(:recipient) { Fabricate(:account, username: 'Barklums') }
     let(:user) { Fabricate(:user) }
-    let(:mail) { described_class.new_pending_account(recipient, user) }
+    let(:mail) { described_class.with(recipient: recipient).new_pending_account(user) }
 
     before do
       recipient.user.update(locale: :en)
@@ -69,7 +69,7 @@ RSpec.describe AdminMailer do
     let(:links) { [] }
     let(:statuses) { [] }
     let(:tags) { [] }
-    let(:mail) { described_class.new_trends(recipient, links, tags, statuses) }
+    let(:mail) { described_class.with(recipient: recipient).new_trends(links, tags, statuses) }
 
     before do
       recipient.user.update(locale: :en)
diff --git a/spec/mailers/previews/admin_mailer_preview.rb b/spec/mailers/previews/admin_mailer_preview.rb
index 9572768cd..bc8f0193b 100644
--- a/spec/mailers/previews/admin_mailer_preview.rb
+++ b/spec/mailers/previews/admin_mailer_preview.rb
@@ -5,16 +5,16 @@
 class AdminMailerPreview < ActionMailer::Preview
   # Preview this email at http://localhost:3000/rails/mailers/admin_mailer/new_pending_account
   def new_pending_account
-    AdminMailer.new_pending_account(Account.first, User.pending.first)
+    AdminMailer.with(recipient: Account.first).new_pending_account(User.pending.first)
   end
 
   # Preview this email at http://localhost:3000/rails/mailers/admin_mailer/new_trends
   def new_trends
-    AdminMailer.new_trends(Account.first, PreviewCard.joins(:trend).limit(3), Tag.limit(3), Status.joins(:trend).where(reblog_of_id: nil).limit(3))
+    AdminMailer.with(recipient: Account.first).new_trends(PreviewCard.joins(:trend).limit(3), Tag.limit(3), Status.joins(:trend).where(reblog_of_id: nil).limit(3))
   end
 
   # Preview this email at http://localhost:3000/rails/mailers/admin_mailer/new_appeal
   def new_appeal
-    AdminMailer.new_appeal(Account.first, Appeal.first)
+    AdminMailer.with(recipient: Account.first).new_appeal(Appeal.first)
   end
 end