diff --git a/docs/release_notes.rst b/docs/release_notes.rst
index ba8c279..20145e1 100644
--- a/docs/release_notes.rst
+++ b/docs/release_notes.rst
@@ -1,6 +1,10 @@
 Release Notes
 =============
 
+v0.14.2
+-------
+* Fix upsert to use the proper prepare method on django fields
+
 v0.14.1
 -------
 * Fix upsert to handle case when the uniqueness constraint is the pk field
diff --git a/querybuilder/query.py b/querybuilder/query.py
index 8303d2c..5663e27 100644
--- a/querybuilder/query.py
+++ b/querybuilder/query.py
@@ -1229,7 +1229,7 @@ def get_upsert_sql(self, rows, unique_fields, update_fields, auto_field_name=Non
             placeholders = []
             for field in all_fields:
                 # Convert field value to db value
-                sql_args.append(field.get_prep_value(getattr(row, field.column)))
+                sql_args.append(field.get_db_prep_save(getattr(row, field.column), self.connection))
                 placeholders.append('%s')
             row_values.append('({0})'.format(', '.join(placeholders)))
         row_values_sql = ', '.join(row_values)
diff --git a/querybuilder/version.py b/querybuilder/version.py
index 092052c..c41af0b 100644
--- a/querybuilder/version.py
+++ b/querybuilder/version.py
@@ -1 +1 @@
-__version__ = '0.14.1'
+__version__ = '0.14.2'