diff --git a/apps/location/models.py b/apps/location/models.py
index 5d5211a5..02e8c6b9 100644
--- a/apps/location/models.py
+++ b/apps/location/models.py
@@ -29,6 +29,7 @@ class Country(TranslatedFieldsMixin,
     """Country model."""
 
     STR_FIELD_NAME = 'name'
+    CALLING_NUMBER_MASK = '+%s'
 
     TWELVE_HOURS_FORMAT_COUNTRIES = [
         'ca',  # Canada
@@ -74,13 +75,24 @@ class Country(TranslatedFieldsMixin,
         return 'hh:mmA'
 
     @property
-    def display_calling_code(self):
+    def display_calling_code(self) -> str:
         """Return formatted calling code."""
         if self.code and self.calling_code:
             # hardcoded calling numbers for Antilles Guyane West Indies islands.
             if self.code.lower() == 'aa':
-                return f'{[f"+{i}" for i in set(settings.CALLING_CODES_ANTILLES_GUYANE_WEST_INDIES)]}'
-            return f'+{self.calling_code}'
+                return f"""{[self.CALLING_NUMBER_MASK % i 
+                             for i in set(settings.CALLING_CODES_ANTILLES_GUYANE_WEST_INDIES)]}"""
+            return self.CALLING_NUMBER_MASK % self.calling_code
+
+    @property
+    def default_calling_code(self):
+        """Return default calling code based on phone number."""
+        if self.code and self.calling_code:
+            # hardcoded default calling number for Antilles Guyane West Indies islands.
+            if self.code.lower() == 'aa':
+                return (self.CALLING_NUMBER_MASK %
+                        settings.DEFAULT_CALLING_CODE_ANTILLES_GUYANE_WEST_INDIES)
+            return self.CALLING_NUMBER_MASK % self.calling_code
 
 
 class RegionQuerySet(models.QuerySet):
diff --git a/apps/location/serializers/back.py b/apps/location/serializers/back.py
index 51163d5a..dc23a727 100644
--- a/apps/location/serializers/back.py
+++ b/apps/location/serializers/back.py
@@ -21,6 +21,7 @@ class CountryBackSerializer(common.CountrySerializer):
             'name',
             'name_translated',
             'display_calling_code',
+            'default_calling_code',
         ]
         extra_kwargs = {
             'calling_code': {'write_only': True}
diff --git a/apps/location/serializers/common.py b/apps/location/serializers/common.py
index 404e415e..5238e132 100644
--- a/apps/location/serializers/common.py
+++ b/apps/location/serializers/common.py
@@ -13,6 +13,7 @@ class CountrySerializer(serializers.ModelSerializer):
 
     name_translated = TranslatedField()
     display_calling_code = serializers.CharField(allow_null=True, read_only=True)
+    default_calling_code = serializers.CharField(allow_null=True, read_only=True)
 
     class Meta:
         model = models.Country
@@ -22,6 +23,7 @@ class CountrySerializer(serializers.ModelSerializer):
             'svg_image',
             'name_translated',
             'display_calling_code',
+            'default_calling_code',
         ]
 
 
diff --git a/project/settings/base.py b/project/settings/base.py
index 8ae06fbc..b6888806 100644
--- a/project/settings/base.py
+++ b/project/settings/base.py
@@ -562,3 +562,4 @@ COUNTRY_CALLING_CODES = {
 }
 
 CALLING_CODES_ANTILLES_GUYANE_WEST_INDIES = [590, 594, 1758]
+DEFAULT_CALLING_CODE_ANTILLES_GUYANE_WEST_INDIES = 590