diff --git a/lemarche/utils/models.py b/lemarche/utils/models.py
new file mode 100644
index 000000000..f4d31833b
--- /dev/null
+++ b/lemarche/utils/models.py
@@ -0,0 +1,10 @@
+def get_object_by_id_or_none(classmodel, id: int | str | None):
+    """
+    https://stackoverflow.com/a/20674112/4293684
+    """
+    if id:
+        try:
+            return classmodel.objects.get(id=int(id))
+        except classmodel.DoesNotExist:
+            pass
+    return None
diff --git a/lemarche/utils/tests_models.py b/lemarche/utils/tests_models.py
new file mode 100644
index 000000000..e1bc9aa00
--- /dev/null
+++ b/lemarche/utils/tests_models.py
@@ -0,0 +1,24 @@
+from django.test import TestCase
+
+from lemarche.siaes.models import Siae
+from lemarche.utils.models import get_object_by_id_or_none
+
+
+class ModelsTest(TestCase):
+    @classmethod
+    def setUpTestData(cls):
+        cls.siae = Siae.objects.create()
+
+    def test_get_object_by_id_or_none(self):
+        # None
+        result = get_object_by_id_or_none(Siae, None)
+        self.assertIsNone(result)
+        # wrong id
+        result = get_object_by_id_or_none(Siae, self.siae.id + 1)
+        self.assertIsNone(result)
+        # id exists (but string)
+        result = get_object_by_id_or_none(Siae, str(self.siae.id))
+        self.assertEqual(result, self.siae)
+        # id exists
+        result = get_object_by_id_or_none(Siae, self.siae.id)
+        self.assertEqual(result, self.siae)