diff --git a/sinch/core/clients/sinch_client_configuration.py b/sinch/core/clients/sinch_client_configuration.py
index 2338749..ca22137 100644
--- a/sinch/core/clients/sinch_client_configuration.py
+++ b/sinch/core/clients/sinch_client_configuration.py
@@ -66,7 +66,7 @@ def __init__(
             self.logger = logging.getLogger("Sinch")
 
     def _set_sms_origin_with_service_plan_id(self):
-        self._sms_origin_with_service_plan_id = self._sms_domain_with_service_plan_id.format(self._sms_region)
+        self.sms_origin_with_service_plan_id = self._sms_domain_with_service_plan_id.format(self._sms_region)
 
     def _set_sms_region_with_service_plan_id(self, region):
         self._sms_region = region
diff --git a/sinch/domains/sms/endpoints/sms_endpoint.py b/sinch/domains/sms/endpoints/sms_endpoint.py
index f678711..89bcb83 100644
--- a/sinch/domains/sms/endpoints/sms_endpoint.py
+++ b/sinch/domains/sms/endpoints/sms_endpoint.py
@@ -12,7 +12,7 @@ def __init__(self, request_data, sinch):
         if sinch.configuration.service_plan_id:
             self.project_or_service_id = sinch.configuration.service_plan_id
             self.HTTP_AUTHENTICATION = HTTPAuthentication.SMS_TOKEN.value
-            self.sms_origin = self.sinch.configuration._sms_origin_with_service_plan_id
+            self.sms_origin = self.sinch.configuration.sms_origin_with_service_plan_id
 
         else:
             self.project_or_service_id = sinch.configuration.project_id
diff --git a/tests/conftest.py b/tests/conftest.py
index 7036a44..d1cc442 100644
--- a/tests/conftest.py
+++ b/tests/conftest.py
@@ -61,7 +61,7 @@ def configure_origin(
 
     if sms_origin:
         sinch_client.configuration.sms_origin = sms_origin
-        sinch_client.configuration._sms_origin_with_service_plan_id = sms_origin
+        sinch_client.configuration.sms_origin_with_service_plan_id = sms_origin
 
     if verification_origin:
         sinch_client.configuration.verification_origin = verification_origin
diff --git a/tests/integration/test_sms_endpoint_credendials_formatting.py b/tests/integration/test_sms_endpoint_credendials_formatting.py
index 70fd6e1..4c8a015 100644
--- a/tests/integration/test_sms_endpoint_credendials_formatting.py
+++ b/tests/integration/test_sms_endpoint_credendials_formatting.py
@@ -10,7 +10,7 @@ def test_sms_endpoint_service_plan_id_credentials_processing(sinch_client_sync_w
     assert sms_endpoint.project_or_service_id == service_plan_id
     assert sms_endpoint.HTTP_AUTHENTICATION == HTTPAuthentication.SMS_TOKEN.value
     assert (
-        sms_endpoint.sms_origin == sinch_client_sync_with_service_plan_id.configuration._sms_origin_with_service_plan_id
+        sms_endpoint.sms_origin == sinch_client_sync_with_service_plan_id.configuration.sms_origin_with_service_plan_id
     )
 
 
diff --git a/tests/unit/test_configuration.py b/tests/unit/test_configuration.py
index 0071ea4..7a1e359 100644
--- a/tests/unit/test_configuration.py
+++ b/tests/unit/test_configuration.py
@@ -30,7 +30,7 @@ def test_set_sms_region_with_service_plan_id_property_and_check_that_sms_origin_
     sinch_client_sync.configuration.sms_region_with_service_plan_id = (
         "Herring"
     )
-    assert sinch_client_sync.configuration._sms_origin_with_service_plan_id.startswith("Herring")
+    assert sinch_client_sync.configuration.sms_origin_with_service_plan_id.startswith("Herring")
 
 
 def test_set_sms_domain_property_and_check_that_sms_origin_was_updated(sinch_client_sync):