diff --git a/app/tasks/maintenance/populate_siret_value_json_task.rb b/app/tasks/maintenance/populate_siret_value_json_task.rb
new file mode 100644
index 000000000..b8531e705
--- /dev/null
+++ b/app/tasks/maintenance/populate_siret_value_json_task.rb
@@ -0,0 +1,18 @@
+# frozen_string_literal: true
+
+module Maintenance
+  class PopulateSiretValueJSONTask < MaintenanceTasks::Task
+    def collection
+      Champs::SiretChamp.where.not(value: nil)
+    end
+
+    def process(champ)
+      return if champ.etablissement.blank?
+      champ.update!(value_json: APIGeoService.parse_etablissement_address(champ.etablissement))
+    end
+
+    def count
+      # not really interested in counting because it raises PG Statement timeout
+    end
+  end
+end
diff --git a/spec/tasks/maintenance/populate_siret_value_json_task_spec.rb b/spec/tasks/maintenance/populate_siret_value_json_task_spec.rb
new file mode 100644
index 000000000..4fca8f9ce
--- /dev/null
+++ b/spec/tasks/maintenance/populate_siret_value_json_task_spec.rb
@@ -0,0 +1,31 @@
+# frozen_string_literal: true
+
+require "rails_helper"
+
+module Maintenance
+  RSpec.describe PopulateSiretValueJSONTask do
+    describe "#process" do
+      let(:procedure) { create(:procedure, types_de_champ_public: [{ type: :siret }]) }
+      let(:dossier) { create(:dossier, :with_populated_champs, procedure:) }
+      let(:element) { dossier.champs.first }
+      subject(:process) { described_class.process(element) }
+
+      it 'updates value_json' do
+        expect { subject }.to change { element.reload.value_json }
+          .from(nil)
+          .to({
+            "city_code" => "92009",
+            "city_name" => "Bois-Colombes",
+            "postal_code" => "92270",
+            "region_code" => "11",
+            "region_name" => "Île-de-France",
+            "street_name" => "RAOUL NORDLING",
+            "street_number" => "6",
+            "street_address" => "6 RUE RAOUL NORDLING",
+            "departement_code" => "92",
+            "departement_name" => "Hauts-de-Seine"
+          })
+      end
+    end
+  end
+end