diff --git a/app/models/dossier.rb b/app/models/dossier.rb
index f4c28c44d..8da633957 100644
--- a/app/models/dossier.rb
+++ b/app/models/dossier.rb
@@ -277,6 +277,23 @@ class Dossier < ApplicationRecord
     DossierMailer.notify_deletion_to_user(deleted_dossier, user.email).deliver_later
   end
 
+  def old_state_value
+    case state
+    when Dossier.states.fetch(:en_construction)
+      'initiated'
+    when Dossier.states.fetch(:en_instruction)
+      'received'
+    when Dossier.states.fetch(:accepte)
+      'closed'
+    when Dossier.states.fetch(:refuse)
+      'refused'
+    when Dossier.states.fetch(:sans_suite)
+      'without_continuation'
+    else
+      state
+    end
+  end
+
   private
 
   def update_state_dates
diff --git a/app/serializers/dossier_serializer.rb b/app/serializers/dossier_serializer.rb
index 05575a90b..252c362e6 100644
--- a/app/serializers/dossier_serializer.rb
+++ b/app/serializers/dossier_serializer.rb
@@ -43,20 +43,7 @@ class DossierSerializer < ActiveModel::Serializer
   end
 
   def state
-    case object.state
-    when Dossier.states.fetch(:en_construction)
-      'initiated'
-    when Dossier.states.fetch(:en_instruction)
-      'received'
-    when Dossier.states.fetch(:accepte)
-      'closed'
-    when Dossier.states.fetch(:refuse)
-      'refused'
-    when Dossier.states.fetch(:sans_suite)
-      'without_continuation'
-    else
-      object.state
-    end
+    object.old_state_value
   end
 
   def simplified_state
diff --git a/app/serializers/dossiers_serializer.rb b/app/serializers/dossiers_serializer.rb
index 98fa3cfb0..a1c225229 100644
--- a/app/serializers/dossiers_serializer.rb
+++ b/app/serializers/dossiers_serializer.rb
@@ -1,9 +1,14 @@
 class DossiersSerializer < ActiveModel::Serializer
   attributes :id,
     :updated_at,
-    :initiated_at
+    :initiated_at,
+    :state
 
   def initiated_at
     object.en_construction_at
   end
+
+  def state
+    object.old_state_value
+  end
 end
diff --git a/spec/controllers/api/v1/dossiers_controller_spec.rb b/spec/controllers/api/v1/dossiers_controller_spec.rb
index de9727fa9..de3ef4f3e 100644
--- a/spec/controllers/api/v1/dossiers_controller_spec.rb
+++ b/spec/controllers/api/v1/dossiers_controller_spec.rb
@@ -77,7 +77,8 @@ describe API::V1::DossiersController do
           it { expect(subject[:id]).to eq(dossier.id) }
           it { expect(subject[:updated_at]).to eq("2008-09-01T10:05:00.000Z") }
           it { expect(subject[:initiated_at]).to eq("2008-09-01T10:06:00.000Z") }
-          it { expect(subject.keys.size).to eq(3) }
+          it { expect(subject[:state]).to eq("initiated") }
+          it { expect(subject.keys.size).to eq(4) }
         end
       end
 
diff --git a/spec/models/dossier_spec.rb b/spec/models/dossier_spec.rb
index 351a890d8..5554f4797 100644
--- a/spec/models/dossier_spec.rb
+++ b/spec/models/dossier_spec.rb
@@ -1004,4 +1004,32 @@ describe Dossier do
       it { expect(long_expired_dossier).to be_retention_expired }
     end
   end
+
+  describe 'old_state_value' do
+    subject { dossier.old_state_value }
+
+    context 'when the dossier is en instruction' do
+      let(:dossier) { create(:dossier, :en_instruction) }
+
+      it { is_expected.to eq('received') }
+    end
+
+    context 'when the dossier is accepte' do
+      let(:dossier) { create(:dossier, state: Dossier.states.fetch(:accepte)) }
+
+      it { is_expected.to eq('closed') }
+    end
+
+    context 'when the dossier is refuse' do
+      let(:dossier) { create(:dossier, state: Dossier.states.fetch(:refuse)) }
+
+      it { is_expected.to eq('refused') }
+    end
+
+    context 'when the dossier is sans_suite' do
+      let(:dossier) { create(:dossier, state: Dossier.states.fetch(:sans_suite)) }
+
+      it { is_expected.to eq('without_continuation') }
+    end
+  end
 end
diff --git a/spec/serializers/dossier_serializer_spec.rb b/spec/serializers/dossier_serializer_spec.rb
index 1de1c5e39..4cf4b398d 100644
--- a/spec/serializers/dossier_serializer_spec.rb
+++ b/spec/serializers/dossier_serializer_spec.rb
@@ -13,25 +13,6 @@ describe DossierSerializer do
       let(:dossier) { create(:dossier, :en_instruction) }
 
       it { is_expected.to include(received_at: dossier.en_instruction_at) }
-      it { is_expected.to include(state: 'received') }
-    end
-
-    context 'when the dossier is accepte' do
-      let(:dossier) { create(:dossier, state: Dossier.states.fetch(:accepte)) }
-
-      it { is_expected.to include(state: 'closed') }
-    end
-
-    context 'when the dossier is refuse' do
-      let(:dossier) { create(:dossier, state: Dossier.states.fetch(:refuse)) }
-
-      it { is_expected.to include(state: 'refused') }
-    end
-
-    context 'when the dossier is sans_suite' do
-      let(:dossier) { create(:dossier, state: Dossier.states.fetch(:sans_suite)) }
-
-      it { is_expected.to include(state: 'without_continuation') }
     end
   end
 end
diff --git a/spec/serializers/dossiers_serializer_spec.rb b/spec/serializers/dossiers_serializer_spec.rb
index f2259574e..1fd01f41e 100644
--- a/spec/serializers/dossiers_serializer_spec.rb
+++ b/spec/serializers/dossiers_serializer_spec.rb
@@ -6,6 +6,7 @@ describe DossiersSerializer do
       let(:dossier) { create(:dossier, :en_construction) }
 
       it { is_expected.to include(initiated_at: dossier.en_construction_at) }
+      it { is_expected.to include(state: 'initiated') }
     end
   end
 end