diff --git a/users/tests/SignupTest.py b/users/tests/test_signup.py
similarity index 72%
rename from users/tests/SignupTest.py
rename to users/tests/test_signup.py
index 6bada2480..3ffb507e9 100644
--- a/users/tests/SignupTest.py
+++ b/users/tests/test_signup.py
@@ -62,3 +62,30 @@ def test_signup_form_with_different_passwords(self) -> None:
             field="password2",
             errors="Les mots de passe ne sont pas identiques",
         )
+
+    def test_allowed_characters_are_accepted(self) -> None:
+        fields_to_test = {
+            "first_name": "John-Doe",
+            "last_name": "John Do'e",
+            "function": "Test",
+        }
+
+        data = {**valid_payload, **fields_to_test}
+
+        response = self.client.post(path=form_url, data=data)
+        self.assertFormError(
+            response=response,
+            form="form",
+            field=None,
+            errors=[],
+        )
+
+    def test_accents_are_accepted(self):
+        data = {**valid_payload, **{"first_name": "Jérôme"}}
+        response = self.client.post(path=form_url, data=data)
+        self.assertFormError(
+            response=response,
+            form="form",
+            field=None,
+            errors=[],
+        )
diff --git a/utils/validators.py b/utils/validators.py
index 9e51b407f..657a32996 100644
--- a/utils/validators.py
+++ b/utils/validators.py
@@ -2,7 +2,8 @@
 
 
 def is_alpha_valid(value: str) -> bool:
-    return all(char.isalpha() or char == " " or char == "-" for char in value)
+    special_chars_allowed = [" ", "-", "'"]
+    return all(char.isalpha() or char in special_chars_allowed for char in value)
 
 
 def is_alpha_validator(value: str) -> bool: