diff --git a/app/controllers/new_administrateur/types_de_champ_controller.rb b/app/controllers/new_administrateur/types_de_champ_controller.rb
index b88cb1642..ea7023757 100644
--- a/app/controllers/new_administrateur/types_de_champ_controller.rb
+++ b/app/controllers/new_administrateur/types_de_champ_controller.rb
@@ -44,7 +44,6 @@ module NewAdministrateur
       {
         type_de_champ: type_de_champ.as_json(
           except: [
-            :id,
             :created_at,
             :options,
             :order_place,
@@ -64,7 +63,7 @@ module NewAdministrateur
             :piece_justificative_template_url,
             :quartiers_prioritaires
           ]
-        ).merge(id: TypeDeChamp.format_stable_id(type_de_champ.stable_id))
+        )
       }
     end
 
diff --git a/app/models/type_de_champ.rb b/app/models/type_de_champ.rb
index e0ff6990d..fff12bd04 100644
--- a/app/models/type_de_champ.rb
+++ b/app/models/type_de_champ.rb
@@ -304,7 +304,7 @@ class TypeDeChamp < ApplicationRecord
 
   def read_attribute_for_serialization(name)
     if name == 'id'
-      self.class.format_stable_id(stable_id)
+      stable_id
     else
       super
     end
@@ -317,15 +317,11 @@ class TypeDeChamp < ApplicationRecord
   # This is only needed for a clean migration without downtime. We want to ensure
   # that if editor send a simple id because it was loaded before deployment
   # we would still do the right thing.
-  def self.format_stable_id(stable_id)
-    "stable:#{stable_id}"
-  end
-
   def self.to_stable_id(id_or_stable_id)
     if id_or_stable_id.to_s =~ /^stable:/
       id_or_stable_id.to_s.gsub(/^stable:/, '')
     else
-      find(id_or_stable_id).stable_id
+      id_or_stable_id
     end
   end