diff --git a/src/frformat/custom_format.py b/src/frformat/custom_format.py
index 9d49e9b..9c0d647 100644
--- a/src/frformat/custom_format.py
+++ b/src/frformat/custom_format.py
@@ -18,6 +18,9 @@ class CustomFormat(ABC, Generic[ValueType]):
     metadata: Metadata
     formatter: Formatter = DefaultFormatter[ValueType]()
 
+    def __init__(self):
+        ...
+
     @abstractmethod
     def is_valid(self, value: ValueType) -> bool:
         ...
diff --git a/src/frformat/enum_format.py b/src/frformat/enum_format.py
index a7613d7..aa43af9 100644
--- a/src/frformat/enum_format.py
+++ b/src/frformat/enum_format.py
@@ -1,4 +1,4 @@
-from typing import Set, Type
+from typing import Optional, Set, Type
 
 from frformat import CustomStrFormat, Metadata
 from frformat.common import normalize_value
@@ -11,20 +11,22 @@ class EnumFormat(CustomStrFormat):
 
         May preprocess the input and valid values according to given "options"."""
 
-        def __init__(self, options: Options):
-            self._options = options
+        def __init__(self, options: Optional[Options] = None):
+            self.options = options if options is not None else Options()
+
             _normalized_extra_values = {
-                normalize_value(e, self._options)
-                for e in self._options.extra_valid_values
+                normalize_value(e, self.options)
+                for e in self.options.extra_valid_values
             }
+
             self._normalized_enum = {
-                normalize_value(e, self._options) for e in enum
+                normalize_value(e, self.options) for e in enum
             }.union(_normalized_extra_values)
 
         metadata = Metadata(name, description)
 
         def is_valid(self, value: str) -> bool:
-            normalized_value = normalize_value(value, self._options)
+            normalized_value = normalize_value(value, self.options)
             return normalized_value in self._normalized_enum
 
     EnumFormat.__name__ = class_name
diff --git a/src/tests/test_geo_fr.py b/src/tests/test_geo_fr.py
index 70f61c0..efa45b0 100644
--- a/src/tests/test_geo_fr.py
+++ b/src/tests/test_geo_fr.py
@@ -15,7 +15,6 @@
     Region,
 )
 from frformat.common import NBSP, NNBSP
-from frformat.options import Options
 from tests.testing import strict_lenient_test_helper_factory
 
 
@@ -29,7 +28,7 @@ def test_code_fantoir():
 
 def test_code_commune_insee():
     value = "01015"
-    code_commune_insee = CodeCommuneInsee(Options())
+    code_commune_insee = CodeCommuneInsee()
     assert code_commune_insee.is_valid(value)
     assert code_commune_insee.format(value) == value
 
@@ -39,7 +38,7 @@ def test_code_commune_insee():
 
 def test_code_postal():
     value = "05560"
-    code_postal = CodePostal(Options())
+    code_postal = CodePostal()
     assert code_postal.is_valid(value)
     assert code_postal.format(value) == value