diff --git a/maxipago/managers/card.py b/maxipago/managers/card.py
index 9d2ad8a..298f2f1 100644
--- a/maxipago/managers/card.py
+++ b/maxipago/managers/card.py
@@ -13,14 +13,14 @@ def add(self, **kwargs):
             ('expiration_month', {'translated_name': 'expirationMonth'}),
             ('expiration_year', {'translated_name': 'expirationYear'}),
             ('billing_name', {'translated_name': 'billingName'}),
-            ('billing_address1', {'translated_name': 'billingAddress1'}),
+            ('billing_address1', {'translated_name': 'billingAddress1', 'required': False}),
             ('billing_address2', {'translated_name': 'billingAddress2', 'required': False}),
-            ('billing_city', {'translated_name': 'billingCity'}),
-            ('billing_state', {'translated_name': 'billingState'}),
-            ('billing_zip', {'translated_name': 'billingZip'}),
-            ('billing_country', {'translated_name': 'billingCountry'}),
-            ('billing_phone', {'translated_name': 'billingPhone'}),
-            ('billing_email', {'translated_name': 'billingEmail'}),
+            ('billing_city', {'translated_name': 'billingCity', 'required': False}),
+            ('billing_state', {'translated_name': 'billingState', 'required': False}),
+            ('billing_zip', {'translated_name': 'billingZip', 'required': False}),
+            ('billing_country', {'translated_name': 'billingCountry', 'required': False}),
+            ('billing_phone', {'translated_name': 'billingPhone', 'required': False}),
+            ('billing_email', {'translated_name': 'billingEmail', 'required': False}),
             ('onfile_end_date', {'translated_name': 'onFileEndDate', 'required': False}),
             ('onfile_permissions', {'translated_name': 'onFilePermissions', 'required': False}),
             ('onfile_comment', {'translated_name': 'onFileComment', 'required': False}),
diff --git a/tests.py b/tests.py
index 35a2217..310c998 100644
--- a/tests.py
+++ b/tests.py
@@ -9,7 +9,10 @@
 
 MAXIPAGO_ID = os.getenv('MAXIPAGO_ID')
 MAXIPAGO_API_KEY = os.getenv('MAXIPAGO_API_KEY')
-
+if not MAXIPAGO_ID:
+    raise ValueError("You must setup the maxipago id env variable.")
+if not MAXIPAGO_API_KEY:
+    raise ValueError("You must setup the maxipago api key env variable.")
 
 class MaxipagoTestCase(unittest.TestCase):
 
@@ -115,6 +118,29 @@ def test_add_card(self):
 
         self.assertTrue(getattr(response, 'token', False))
 
+    def test_add_card_minimal_fields(self):
+        CUSTOMER_ID = randint(1, 100000)
+
+        response = self.maxipago.customer.add(
+            customer_id=CUSTOMER_ID,
+            first_name=u'Fulano',
+            last_name=u'de Tal',
+        )
+
+        self.assertTrue(hasattr(response, 'id'))
+
+        maxipago_customer_id = response.id
+
+        response = self.maxipago.card.add(
+            customer_id=maxipago_customer_id,
+            number=u'4111111111111111',
+            expiration_month=u'02',
+            expiration_year=date.today().year + 3,
+            billing_name=u'Fulano de Tal',
+        )
+
+        self.assertTrue(getattr(response, 'token', False))
+
     def test_delete_card(self):
         CUSTOMER_ID = randint(1, 100000)