diff --git a/Gemfile b/Gemfile
index b52a299cd..10c680786 100644
--- a/Gemfile
+++ b/Gemfile
@@ -94,6 +94,9 @@ gem 'uuidtools', '2.1.5' # For unique IDs (used by the epp gem)
 gem 'que',           '0.10.0'
 gem 'que-web',       '0.4.0'
 gem 'daemons-rails', '1.2.1'
+gem 'que_mailer',
+    github: 'prehnRA/que-mailer',
+    branch: 'master'
 
 # for importing legacy db
 gem 'activerecord-import', '0.7.0' # for inserting dummy data
diff --git a/app/jobs/domain_delete_confirm_job.rb b/app/jobs/domain_delete_confirm_job.rb
index 7d890ef16..aa3effb12 100644
--- a/app/jobs/domain_delete_confirm_job.rb
+++ b/app/jobs/domain_delete_confirm_job.rb
@@ -9,7 +9,7 @@ class DomainDeleteConfirmJob < Que::Job
         domain.apply_pending_delete!
         domain.clean_pendings!
       when RegistrantVerification::REJECTED
-        DomainMailer.pending_delete_rejected_notification(domain).deliver_now
+        DomainMailer.pending_delete_rejected_notification(domain_id).deliver
         domain.statuses.delete(DomainStatus::PENDING_DELETE_CONFIRMATION)
         domain.poll_message!(:poll_pending_delete_rejected_by_registrant)
         domain.clean_pendings!
diff --git a/app/jobs/domain_update_confirm_job.rb b/app/jobs/domain_update_confirm_job.rb
index f6e28e2c3..28294ef25 100644
--- a/app/jobs/domain_update_confirm_job.rb
+++ b/app/jobs/domain_update_confirm_job.rb
@@ -11,7 +11,7 @@ class DomainUpdateConfirmJob < Que::Job
         end
         domain.clean_pendings!
       when RegistrantVerification::REJECTED
-        DomainMailer.pending_update_rejected_notification_for_new_registrant(domain).deliver_now
+        DomainMailer.pending_update_rejected_notification_for_new_registrant(domain_id).deliver
         domain.poll_message!(:poll_pending_update_rejected_by_registrant)
         domain.clean_pendings!
         domain.instance_variable_set("@changed_attributes", domain.changed_attributes.merge("statuses"=>[]))
diff --git a/app/mailers/contact_mailer.rb b/app/mailers/contact_mailer.rb
index 2f8de7248..2f858a585 100644
--- a/app/mailers/contact_mailer.rb
+++ b/app/mailers/contact_mailer.rb
@@ -1,10 +1,12 @@
 class ContactMailer < ApplicationMailer
-  def email_updated(email, contact)
+  include Que::Mailer
+
+  def email_updated(email, contact_id)
+    @contact = Contact.find_by(id: contact_id)
+    return unless email || @contact
     return if delivery_off?(contact)
-
-    @contact = contact
-
     return if whitelist_blocked?(email)
+
     begin
       mail(to: format(email), subject: "#{I18n.t(:contact_email_update_subject)} [#{@contact.code}]")
     rescue EOFError,
diff --git a/app/mailers/domain_mailer.rb b/app/mailers/domain_mailer.rb
index a8c79f66d..70f5d8f39 100644
--- a/app/mailers/domain_mailer.rb
+++ b/app/mailers/domain_mailer.rb
@@ -1,6 +1,9 @@
 class DomainMailer < ApplicationMailer
-  def pending_update_request_for_old_registrant(domain)
-    @domain = domain
+  include Que::Mailer
+
+  def pending_update_request_for_old_registrant(domain_id)
+    @domain = Domain.find_by(id: domain_id)
+    return unless @domain
     return if delivery_off?(@domain)
 
     if @domain.registrant_verification_token.blank?
@@ -24,8 +27,9 @@ class DomainMailer < ApplicationMailer
          name: @domain.name)} [#{@domain.name}]")
   end
 
-  def pending_update_notification_for_new_registrant(domain)
-    @domain = domain
+  def pending_update_notification_for_new_registrant(domain_id)
+    @domain = Domain.find_by(id: domain_id)
+    return unless @domain
     return if delivery_off?(@domain)
 
     if @domain.registrant_verification_token.blank?
@@ -47,8 +51,9 @@ class DomainMailer < ApplicationMailer
          name: @domain.name)} [#{@domain.name}]")
   end
 
-  def registrant_updated_notification_for_new_registrant(domain)
-    @domain = domain
+  def registrant_updated_notification_for_new_registrant(domain_id)
+    @domain = Domain.find_by(id: domain_id)
+    return unless @domain
     return if delivery_off?(@domain)
 
     return if whitelist_blocked?(@domain.registrant_email)
@@ -57,8 +62,9 @@ class DomainMailer < ApplicationMailer
          name: @domain.name)} [#{@domain.name}]")
   end
 
-  def registrant_updated_notification_for_old_registrant(domain)
-    @domain = domain
+  def registrant_updated_notification_for_old_registrant(domain_id)
+    domain = Domain.find_by(id: domain_id)
+    return unless domain
     return if delivery_off?(@domain)
 
     @old_registrant_email = domain.registrant_email # Nb! before applying pending updates
@@ -69,8 +75,9 @@ class DomainMailer < ApplicationMailer
          name: @domain.name)} [#{@domain.name}]")
   end
 
-  def pending_update_rejected_notification_for_new_registrant(domain)
-    @domain = domain
+  def pending_update_rejected_notification_for_new_registrant(domain_id)
+    @domain = Domain.find_by(id: domain_id)
+    return unless @domain
     # no delivery off control, driggered by que, no epp request
 
     @new_registrant_email = @domain.pending_json['new_registrant_email']
@@ -82,8 +89,9 @@ class DomainMailer < ApplicationMailer
          name: @domain.name)} [#{@domain.name}]")
   end
 
-  def pending_update_expired_notification_for_new_registrant(domain)
-    @domain = domain
+  def pending_update_expired_notification_for_new_registrant(domain_id)
+    @domain = Domain.find_by(id: domain_id)
+    return unless @domain
     # no delivery off control, driggered by cron, no epp request
 
     @new_registrant_email = @domain.pending_json['new_registrant_email']
@@ -99,8 +107,9 @@ class DomainMailer < ApplicationMailer
          name: @domain.name)} [#{@domain.name}]")
   end
 
-  def pending_deleted(domain)
-    @domain = domain
+  def pending_deleted(domain_id)
+    @domain = Domain.find_by(id: domain_id)
+    return unless @domain
     return if delivery_off?(@domain)
 
     if @domain.registrant_verification_token.blank?
@@ -124,8 +133,10 @@ class DomainMailer < ApplicationMailer
          name: @domain.name)} [#{@domain.name}]")
   end
 
-  def pending_delete_rejected_notification(domain)
-    @domain = domain
+  def pending_delete_rejected_notification(domain_id)
+    @domain = Domain.find_by(id: domain_id)
+    return unless @domain
+    return if delivery_off?(@domain)
     # no delivery off control, driggered by que, no epp request
 
     if @domain.registrant_verification_token.blank?
@@ -144,8 +155,10 @@ class DomainMailer < ApplicationMailer
          name: @domain.name)} [#{@domain.name}]")
   end
 
-  def pending_delete_expired_notification(domain)
-    @domain = domain
+  def pending_delete_expired_notification(domain_id)
+    @domain = Domain.find_by(id: domain_id)
+    return unless @domain
+    return if delivery_off?(@domain)
     # no delivery off control, driggered by cron, no epp request
 
     return if whitelist_blocked?(@domain.registrant.email)
@@ -154,8 +167,10 @@ class DomainMailer < ApplicationMailer
          name: @domain.name)} [#{@domain.name}]")
   end
 
-  def delete_confirmation(domain)
-    @domain = domain
+  def delete_confirmation(domain_id)
+    @domain = Domain.find_by(id: domain_id)
+    return unless @domain
+    return if delivery_off?(@domain)
 
     return if whitelist_blocked?(@domain.registrant.email)
     mail(to: format(@domain.registrant.email),
@@ -163,8 +178,9 @@ class DomainMailer < ApplicationMailer
          name: @domain.name)} [#{@domain.name}]")
   end
 
-  def force_delete(domain)
-    @domain = domain
+  def force_delete(domain_id)
+    @domain = Domain.find_by(id: domain_id)
+    return if delivery_off?(@domain)
     emails = ([@domain.registrant.email] + @domain.admin_contacts.map { |x| format(x.email) }).uniq
     return if whitelist_blocked?(emails)
 
diff --git a/app/mailers/invoice_mailer.rb b/app/mailers/invoice_mailer.rb
index e78795b66..54c6a8605 100644
--- a/app/mailers/invoice_mailer.rb
+++ b/app/mailers/invoice_mailer.rb
@@ -1,8 +1,15 @@
 class InvoiceMailer < ApplicationMailer
-  def invoice_email(invoice, pdf)
-    return if whitelist_blocked?(invoice.billing_email)
+  include Que::Mailer
+
+  def invoice_email(invoice_id, html)
+    @invoice = Invoice.find_by(id: invoice_id)
+    return unless @invoice
+    return if whitelist_blocked?(@invoice.billing_email)
+
+    kit = PDFKit.new(html)
+    pdf = kit.to_pdf
+    invoice = @invoice
 
-    @invoice = invoice
     attachments[invoice.pdf_name] = pdf
     mail(to: format(invoice.billing_email), subject: invoice)
   end
diff --git a/app/models/contact.rb b/app/models/contact.rb
index f332dc2c4..9f623a262 100644
--- a/app/models/contact.rb
+++ b/app/models/contact.rb
@@ -50,7 +50,7 @@ class Contact < ActiveRecord::Base
     emails << domains.map(&:registrant_email) if domains.present?
     emails = emails.flatten.uniq
     emails.each do |e|
-      ContactMailer.email_updated(e, self).deliver_now
+      ContactMailer.email_updated(e, id).deliver
     end
   end
 
diff --git a/app/models/domain.rb b/app/models/domain.rb
index 9845e8ac8..8d02f7f83 100644
--- a/app/models/domain.rb
+++ b/app/models/domain.rb
@@ -238,10 +238,10 @@ class Domain < ActiveRecord::Base
         end
         count += 1
         if domain.pending_update?
-          DomainMailer.pending_update_expired_notification_for_new_registrant(domain).deliver_now
+          DomainMailer.pending_update_expired_notification_for_new_registrant(id).deliver
         end
         if domain.pending_delete? || domain.pending_delete_confirmation?
-          DomainMailer.pending_delete_expired_notification(domain).deliver_now
+          DomainMailer.pending_delete_expired_notification(id).deliver
         end
         domain.clean_pendings!
         unless Rails.env.test?
@@ -428,8 +428,8 @@ class Domain < ActiveRecord::Base
     new_registrant_email = registrant.email
     new_registrant_name  = registrant.name
 
-    DomainMailer.pending_update_request_for_old_registrant(self).deliver_now
-    DomainMailer.pending_update_notification_for_new_registrant(self).deliver_now
+    DomainMailer.pending_update_request_for_old_registrant(id).deliver
+    DomainMailer.pending_update_notification_for_new_registrant(id).deliver
 
     reload # revert back to original
 
@@ -489,7 +489,7 @@ class Domain < ActiveRecord::Base
     pending_delete_confirmation!
     save(validate: false) # should check if this did succeed
 
-    DomainMailer.pending_deleted(self).deliver_now
+    DomainMailer.pending_deleted(id).deliver
   end
 
   def pricelist(operation, period_i = nil, unit = nil)
@@ -619,7 +619,7 @@ class Domain < ActiveRecord::Base
       registrar.messages.create!(
         body: I18n.t('force_delete_set_on_domain', domain: name)
       )
-      DomainMailer.force_delete(self).deliver_now
+      DomainMailer.force_delete(id).deliver
       return true
     end
     false
diff --git a/app/models/epp/domain.rb b/app/models/epp/domain.rb
index ffd525d9d..f31105f4d 100644
--- a/app/models/epp/domain.rb
+++ b/app/models/epp/domain.rb
@@ -478,7 +478,7 @@ class Epp::Domain < Domain
   # rubocop: enable Metrics/CyclomaticComplexity
 
   def apply_pending_update!
-    old_registrant_email = DomainMailer.registrant_updated_notification_for_old_registrant(self)
+    old_registrant_email = DomainMailer.registrant_updated_notification_for_old_registrant(id)
     preclean_pendings
     user  = ApiUser.find(pending_json['current_user_id'])
     frame = Nokogiri::XML(pending_json['frame'])
@@ -488,8 +488,8 @@ class Epp::Domain < Domain
     return unless update(frame, user, false)
     clean_pendings!
     self.deliver_emails = true # turn on email delivery
-    DomainMailer.registrant_updated_notification_for_new_registrant(self).deliver_now
-    old_registrant_email.deliver_now
+    DomainMailer.registrant_updated_notification_for_new_registrant(id).deliver
+    old_registrant_email.deliver
     true
   end
 
@@ -497,7 +497,7 @@ class Epp::Domain < Domain
     preclean_pendings
     statuses.delete(DomainStatus::PENDING_DELETE_CONFIRMATION)
     statuses.delete(DomainStatus::PENDING_DELETE)
-    DomainMailer.delete_confirmation(self).deliver_now
+    DomainMailer.delete_confirmation(id).deliver
 
     # TODO: confirm that this actually makes sense
     clean_pendings! if valid? && set_pending_delete!
diff --git a/app/models/invoice.rb b/app/models/invoice.rb
index 583f26825..0c4e23a08 100644
--- a/app/models/invoice.rb
+++ b/app/models/invoice.rb
@@ -117,7 +117,7 @@ class Invoice < ActiveRecord::Base
     return false unless valid?
     return false unless billing_email.present?
 
-    InvoiceMailer.invoice_email(self, pdf(html)).deliver_now
+    InvoiceMailer.invoice_email(id, html).deliver
     true
   end
 
diff --git a/spec/mailers/contact_mailer_spec.rb b/spec/mailers/contact_mailer_spec.rb
index 033843b50..f0402e3db 100644
--- a/spec/mailers/contact_mailer_spec.rb
+++ b/spec/mailers/contact_mailer_spec.rb
@@ -8,7 +8,7 @@ describe ContactMailer do
   describe 'email changed notification when delivery turned off' do
     before :all do
       @contact = Fabricate(:contact, email: 'test@example.ee')
-      @mail = ContactMailer.email_updated('test@example.com', @contact)
+      @mail = ContactMailer.email_updated('test@example.com', @contact.id)
     end
 
     it 'should not render email subject' do
@@ -34,7 +34,7 @@ describe ContactMailer do
       @contact = @domain.registrant
       @contact.reload # until figured out why registrant_domains not loaded
       @contact.deliver_emails = true
-      @mail = ContactMailer.email_updated('info@example.org', @contact)
+      @mail = ContactMailer.email_updated('info@example.org', @contact.id)
     end
 
     it 'should render email subject' do
@@ -60,7 +60,7 @@ describe ContactMailer do
       @contact = @domain.registrant
       @contact.reload # until figured out why registrant_domains not loaded
       @contact.deliver_emails = true
-      @mail = ContactMailer.email_updated('info@ääöü.org', @contact)
+      @mail = ContactMailer.email_updated('info@ääöü.org', @contact.id)
     end
 
     it 'should render email subject' do
diff --git a/spec/mailers/domain_mailer_spec.rb b/spec/mailers/domain_mailer_spec.rb
index 71ed183ce..20662a2ba 100644
--- a/spec/mailers/domain_mailer_spec.rb
+++ b/spec/mailers/domain_mailer_spec.rb
@@ -9,7 +9,7 @@ describe DomainMailer do
     before :all do
       @registrant = Fabricate(:registrant, email: 'test@example.com')
       @domain = Fabricate(:domain, registrant: @registrant)
-      @mail = DomainMailer.pending_update_request_for_old_registrant(@domain)
+      @mail = DomainMailer.pending_update_request_for_old_registrant(@domain.id)
     end
 
     it 'should not render email subject' do
@@ -38,7 +38,7 @@ describe DomainMailer do
       @domain.registrant_verification_token = '123'
       @domain.registrant_verification_asked_at = Time.zone.now
       @domain.registrant = @new_registrant
-      @mail = DomainMailer.pending_update_request_for_old_registrant(@domain)
+      @mail = DomainMailer.pending_update_request_for_old_registrant(@domain.id)
     end
 
     it 'should render email subject' do
@@ -71,7 +71,7 @@ describe DomainMailer do
       @domain.registrant_verification_token = '123'
       @domain.registrant_verification_asked_at = Time.zone.now
       @domain.registrant = @new_registrant
-      @mail = DomainMailer.pending_update_notification_for_new_registrant(@domain)
+      @mail = DomainMailer.pending_update_notification_for_new_registrant(@domain.id)
     end
 
     it 'should render email subject' do
@@ -100,7 +100,7 @@ describe DomainMailer do
       @domain.registrant_verification_token = '123'
       @domain.registrant_verification_asked_at = Time.zone.now
       @domain.registrant = @new_registrant
-      @mail = DomainMailer.pending_update_notification_for_new_registrant(@domain)
+      @mail = DomainMailer.pending_update_notification_for_new_registrant(@domain.id)
     end
 
     it 'should render email subject' do
@@ -128,7 +128,7 @@ describe DomainMailer do
       @domain.deliver_emails = true
       @domain.pending_json['new_registrant_email'] = 'new@example.org'
       @domain.pending_json['new_registrant_name']  = 'test name'
-      @mail = DomainMailer.pending_update_rejected_notification_for_new_registrant(@domain)
+      @mail = DomainMailer.pending_update_rejected_notification_for_new_registrant(@domain.id)
     end
 
     it 'should render email subject' do
@@ -153,7 +153,7 @@ describe DomainMailer do
       @registrant = Fabricate(:registrant, email: 'test@example.com')
       @domain = Fabricate(:domain, registrant: @registrant)
       @domain.deliver_emails = true
-      @mail = DomainMailer.registrant_updated_notification_for_new_registrant(@domain)
+      @mail = DomainMailer.registrant_updated_notification_for_new_registrant(@domain.id)
     end
 
     it 'should render email subject' do
@@ -178,7 +178,7 @@ describe DomainMailer do
       @registrant = Fabricate(:registrant, email: 'test@example.com')
       @domain = Fabricate(:domain, registrant: @registrant)
       @domain.deliver_emails = true
-      @mail = DomainMailer.registrant_updated_notification_for_old_registrant(@domain)
+      @mail = DomainMailer.registrant_updated_notification_for_old_registrant(@domain.id)
     end
 
     it 'should render email subject' do
@@ -202,7 +202,7 @@ describe DomainMailer do
     before :all do
       @registrant = Fabricate(:registrant, email: 'test@example.com')
       @domain = Fabricate(:domain, registrant: @registrant)
-      @mail = DomainMailer.pending_deleted(@domain)
+      @mail = DomainMailer.pending_deleted(@domain.id)
     end
 
     it 'should not render email subject' do
@@ -229,7 +229,7 @@ describe DomainMailer do
       @domain.deliver_emails = true
       @domain.registrant_verification_token = '123'
       @domain.registrant_verification_asked_at = Time.zone.now
-      @mail = DomainMailer.pending_deleted(@domain)
+      @mail = DomainMailer.pending_deleted(@domain.id)
     end
 
     it 'should render email subject' do
@@ -260,7 +260,7 @@ describe DomainMailer do
       @domain.deliver_emails = true
       @domain.registrant_verification_token = '123'
       @domain.registrant_verification_asked_at = Time.zone.now
-      @mail = DomainMailer.pending_delete_rejected_notification(@domain)
+      @mail = DomainMailer.pending_delete_rejected_notification(@domain.id)
     end
 
     it 'should render email subject' do
@@ -287,7 +287,7 @@ describe DomainMailer do
       @domain.deliver_emails = true
       @domain.registrant_verification_token = '123'
       @domain.registrant_verification_asked_at = Time.zone.now
-      @mail = DomainMailer.pending_delete_expired_notification(@domain)
+      @mail = DomainMailer.pending_delete_expired_notification(@domain.id)
     end
 
     it 'should render email subject' do
@@ -314,7 +314,7 @@ describe DomainMailer do
       @domain.deliver_emails = true
       @domain.registrant_verification_token = '123'
       @domain.registrant_verification_asked_at = Time.zone.now
-      @mail = DomainMailer.delete_confirmation(@domain)
+      @mail = DomainMailer.delete_confirmation(@domain.id)
     end
 
     it 'should render email subject' do