diff --git a/modules/marketing_campaign/marketing.py b/modules/marketing_campaign/marketing.py
index b121795864..db95577106 100644
--- a/modules/marketing_campaign/marketing.py
+++ b/modules/marketing_campaign/marketing.py
@@ -134,11 +134,12 @@ class MarketingCampaignMixin(Model):
                     yield fname
 
     @classmethod
-    def default_get(cls, fields_names, with_rec_name=True, with_default=True):
+    def default_get(
+            cls, fields_names=None, with_rec_name=True, with_default=True):
         transaction = Transaction()
         context = transaction.context
         default = super().default_get(
-            fields_names,
+            fields_names=fields_names,
             with_rec_name=with_rec_name,
             with_default=with_default)
         for fname in cls.marketing_campaign_fields():
diff --git a/modules/marketing_campaign/sale_opportunity_reporting.py b/modules/marketing_campaign/sale_opportunity_reporting.py
index c5f551c9d6..b1ace51435 100644
--- a/modules/marketing_campaign/sale_opportunity_reporting.py
+++ b/modules/marketing_campaign/sale_opportunity_reporting.py
@@ -55,11 +55,12 @@ class Context(MarketingCampaignMixin, metaclass=PoolMeta):
     __name__ = 'sale.opportunity.reporting.context'
 
     @classmethod
-    def default_get(cls, fields_names, with_rec_name=True, with_default=True):
+    def default_get(
+            cls, fields_names=None, with_rec_name=True, with_default=True):
         transaction = Transaction()
         context = transaction.context
         default = super().default_get(
-            fields_names,
+            fields_names=fields_names,
             with_rec_name=with_rec_name,
             with_default=with_default)
         for fname in cls.marketing_campaign_fields():
diff --git a/modules/marketing_campaign/sale_reporting.py b/modules/marketing_campaign/sale_reporting.py
index d2dc88cf6e..9800c10d46 100644
--- a/modules/marketing_campaign/sale_reporting.py
+++ b/modules/marketing_campaign/sale_reporting.py
@@ -56,11 +56,12 @@ class Context(MarketingCampaignMixin, metaclass=PoolMeta):
     __name__ = 'sale.reporting.context'
 
     @classmethod
-    def default_get(cls, fields_names, with_rec_name=True, with_default=True):
+    def default_get(
+            cls, fields_names=None, with_rec_name=True, with_default=True):
         transaction = Transaction()
         context = transaction.context
         default = super().default_get(
-            fields_names,
+            fields_names=fields_names,
             with_rec_name=with_rec_name,
             with_default=with_default)
         for fname in cls.marketing_campaign_fields():
diff --git a/modules/party/party.py b/modules/party/party.py
index c12d10eee6..7d1ca47b70 100644
--- a/modules/party/party.py
+++ b/modules/party/party.py
@@ -390,12 +390,13 @@ class Party(
         return result
 
     @classmethod
-    def default_get(cls, fields_names, with_rec_name=True, with_default=True):
+    def default_get(
+            cls, fields_names=None, with_rec_name=True, with_default=True):
         pool = Pool()
         Country = pool.get('country.country')
 
         values = super().default_get(
-            fields_names,
+            fields_names=fields_names,
             with_rec_name=with_rec_name,
             with_default=with_default)
         eu_vat = get_cc_module('eu', 'vat')
diff --git a/trytond/CHANGELOG b/trytond/CHANGELOG
index 366925ebfa..3131395a7c 100644
--- a/trytond/CHANGELOG
+++ b/trytond/CHANGELOG
@@ -1,3 +1,4 @@
+* Make field_names optional in Model.default_get
 * Remove check_xml_record from ModelStorage
 * Always synchronize XML data with database
 * Convert None as empty string when searching on Char or Text
diff --git a/trytond/doc/ref/models.rst b/trytond/doc/ref/models.rst
index 72077470ef..7263c80390 100644
--- a/trytond/doc/ref/models.rst
+++ b/trytond/doc/ref/models.rst
@@ -85,10 +85,10 @@ Class methods:
    <model-ir.model.field>`.
    See :meth:`trytond.pool.PoolBase.__register__`.
 
-.. classmethod:: Model.default_get(fields_names[[, with_rec_name], with_default])
+.. classmethod:: Model.default_get([fields_names[[, with_rec_name], with_default]])
 
    Return a dictionary with the default values for each field in
-   ``fields_names``.
+   ``fields_names`` or all fields if not specified.
    Default values are defined by the returned value of each class method with
    the pattern ``default_<field name>()``.
 
diff --git a/trytond/trytond/model/model.py b/trytond/trytond/model/model.py
index fede417cff..0587b0868d 100644
--- a/trytond/trytond/model/model.py
+++ b/trytond/trytond/model/model.py
@@ -131,7 +131,8 @@ class Model(URLMixin, PoolBase, metaclass=ModelMeta):
         Translation.register_fields(cls, module_name)
 
     @classmethod
-    def default_get(cls, fields_names, with_rec_name=True, with_default=True):
+    def default_get(
+            cls, fields_names=None, with_rec_name=True, with_default=True):
         '''
         Return a dict with the default values for each field in fields_names.
         If with_rec_name is True, rec_name will be added.
@@ -140,6 +141,9 @@ class Model(URLMixin, PoolBase, metaclass=ModelMeta):
         values = {}
         context = Transaction().context
 
+        if fields_names is None:
+            fields_names = cls._fields.keys()
+
         default_rec_name = context.get('default_rec_name')
         if (default_rec_name
                 and cls._rec_name in cls._fields