diff --git a/app/mailers/invite_mailer.rb b/app/mailers/invite_mailer.rb
index d9c892b91..a769d5458 100644
--- a/app/mailers/invite_mailer.rb
+++ b/app/mailers/invite_mailer.rb
@@ -28,6 +28,8 @@ class InviteMailer < ApplicationMailer
     @invite = invite
     email = invite.email
 
+    configure_defaults_for_email(email)
+
     mail(to: email,
       subject: subject,
       reply_to: reply_to)
diff --git a/app/mailers/user_mailer.rb b/app/mailers/user_mailer.rb
index 0989b41c6..f45892699 100644
--- a/app/mailers/user_mailer.rb
+++ b/app/mailers/user_mailer.rb
@@ -9,6 +9,8 @@ class UserMailer < ApplicationMailer
     @subject = "Demande de création de compte"
     @procedure = procedure
 
+    configure_defaults_for_user(user)
+
     mail(to: user.email, subject: @subject, procedure: @procedure)
   end
 
@@ -17,6 +19,8 @@ class UserMailer < ApplicationMailer
     @requested_email = requested_email
     @subject = "Fusion de compte"
 
+    configure_defaults_for_email(requested_email)
+
     mail(to: requested_email, subject: @subject)
   end
 
@@ -25,6 +29,8 @@ class UserMailer < ApplicationMailer
     @email_merge_token_created_at = email_merge_token_created_at
     @subject = "Veuillez confirmer la fusion de compte"
 
+    configure_defaults_for_email(email)
+
     mail(to: email, subject: @subject)
   end
 
@@ -33,9 +39,11 @@ class UserMailer < ApplicationMailer
     @user = user
     subject = "Activez votre compte instructeur"
 
+    configure_defaults_for_user(user)
+
     mail(to: user.email,
       subject: subject,
-      reply_to: CONTACT_EMAIL)
+      reply_to: Current.contact_email)
   end
 
   def invite_gestionnaire(user, reset_password_token, groupe_gestionnaire)
@@ -44,12 +52,16 @@ class UserMailer < ApplicationMailer
     @groupe_gestionnaire = groupe_gestionnaire
     subject = "Activez votre compte gestionnaire"
 
+    configure_defaults_for_user(user)
+
     mail(to: user.email,
       subject: subject,
-      reply_to: CONTACT_EMAIL)
+      reply_to: Current.contact_email)
   end
 
   def send_archive(administrateur_or_instructeur, procedure, archive)
+    configure_defaults_for_user(administrateur_or_instructeur.user)
+
     @archive = archive
     @procedure = procedure
     @archive_url = case administrateur_or_instructeur
@@ -71,6 +83,8 @@ class UserMailer < ApplicationMailer
     @user = user
     @subject = "Votre compte sera supprimé dans #{Expired::REMAINING_WEEKS_BEFORE_EXPIRATION} semaines"
 
+    configure_defaults_for_user(user)
+
     mail(to: user.email, subject: @subject)
   end
 
@@ -80,6 +94,8 @@ class UserMailer < ApplicationMailer
     @procedure = procedure
     @content = content
 
+    configure_defaults_for_user(user)
+
     mail(to: user.email, subject: @subject, content: @content, procedure: @procedure)
   end
 
diff --git a/spec/mailers/user_mailer_spec.rb b/spec/mailers/user_mailer_spec.rb
index 3bd017852..0ae0bc594 100644
--- a/spec/mailers/user_mailer_spec.rb
+++ b/spec/mailers/user_mailer_spec.rb
@@ -13,7 +13,16 @@ RSpec.describe UserMailer, type: :mailer do
 
       subject { described_class.new_account_warning(user, procedure) }
 
-      it { expect(subject.body).to have_link("Commencer la démarche « #{procedure.libelle} »", href: commencer_sign_in_url(path: procedure.path)) }
+      it { expect(subject.body).to have_link("Commencer la démarche « #{procedure.libelle} »", href: commencer_sign_in_url(path: procedure.path, host: ENV.fetch("APP_HOST_LEGACY"))) }
+
+      context "when user has preferred domain" do
+        let(:user) { create(:user, preferred_domain: :demarches_gouv_fr) }
+
+        it do
+          expect(subject.body).to have_link("Commencer la démarche « #{procedure.libelle} »", href: commencer_sign_in_url(path: procedure.path, host: ENV.fetch("APP_HOST")))
+          expect(header_value("From", subject)).to include("@demarches.gouv.fr")
+        end
+      end
     end
 
     context 'without SafeMailer configured' do
@@ -65,7 +74,7 @@ RSpec.describe UserMailer, type: :mailer do
     subject { described_class.france_connect_merge_confirmation(email, code, 15.minutes.from_now) }
 
     it { expect(subject.to).to eq([email]) }
-    it { expect(subject.body).to include(france_connect_particulier_mail_merge_with_existing_account_url(email_merge_token: code)) }
+    it { expect(subject.body).to include(france_connect_particulier_mail_merge_with_existing_account_url(email_merge_token: code))) }
 
     context 'without SafeMailer configured' do
       it { expect(subject[BalancerDeliveryMethod::FORCE_DELIVERY_METHOD_HEADER]&.value).to eq(nil) }
@@ -92,15 +101,15 @@ RSpec.describe UserMailer, type: :mailer do
     context 'instructeur' do
       let(:role) { create(:instructeur) }
       it { expect(subject.to).to eq([role.user.email]) }
-      it { expect(subject.body).to have_link('Consulter mes archives', href: instructeur_archives_url(procedure)) }
-      it { expect(subject.body).to have_link("#{procedure.id} − #{procedure.libelle}", href: instructeur_procedure_url(procedure)) }
+      it { expect(subject.body).to have_link('Consulter mes archives', href: instructeur_archives_url(procedure, host: ENV.fetch("APP_HOST_LEGACY"))) }
+      it { expect(subject.body).to have_link("#{procedure.id} − #{procedure.libelle}", href: instructeur_procedure_url(procedure, host: ENV.fetch("APP_HOST_LEGACY"))) }
     end
 
     context 'instructeur' do
       let(:role) { create(:administrateur) }
       it { expect(subject.to).to eq([role.user.email]) }
-      it { expect(subject.body).to have_link('Consulter mes archives', href: admin_procedure_archives_url(procedure)) }
-      it { expect(subject.body).to have_link("#{procedure.id} − #{procedure.libelle}", href: admin_procedure_url(procedure)) }
+      it { expect(subject.body).to have_link('Consulter mes archives', href: admin_procedure_archives_url(procedure, host: ENV.fetch("APP_HOST_LEGACY"))) }
+      it { expect(subject.body).to have_link("#{procedure.id} − #{procedure.libelle}", href: admin_procedure_url(procedure, host: ENV.fetch("APP_HOST_LEGACY"))) }
     end
 
     context 'when perform_later is called' do