diff --git a/app/models.py b/app/models.py
index 337ea89ae..669fb12f9 100644
--- a/app/models.py
+++ b/app/models.py
@@ -830,12 +830,11 @@ class Notification(db.Model):
     def personalisation(self):
         if self._personalisation:
             return encryption.decrypt(self._personalisation)
-        return None
+        return {}
 
     @personalisation.setter
     def personalisation(self, personalisation):
-        if personalisation:
-            self._personalisation = encryption.encrypt(personalisation)
+        self._personalisation = encryption.encrypt(personalisation or {})
 
     def completed_at(self):
         if self.status in NOTIFICATION_STATUS_TYPES_COMPLETED:
diff --git a/tests/app/test_model.py b/tests/app/test_model.py
index 14fa5609f..d662c6670 100644
--- a/tests/app/test_model.py
+++ b/tests/app/test_model.py
@@ -2,6 +2,7 @@ import pytest
 
 from freezegun import freeze_time
 
+from app import encryption
 from app.models import (
     ServiceWhitelist,
     Notification,
@@ -145,3 +146,23 @@ def test_notification_for_csv_returns_bst_correctly(notify_db, notify_db_session
 
     serialized = notification.serialize_for_csv()
     assert serialized['created_at'] == 'Monday 27 March 2017 at 00:01'
+
+
+def test_notification_personalisation_getter_returns_empty_dict_from_None(sample_notification):
+    sample_notification._personalisation = None
+    assert sample_notification.personalisation == {}
+
+
+def test_notification_personalisation_getter_always_returns_empty_dict(sample_notification):
+    sample_notification._personalisation = encryption.encrypt({})
+    assert sample_notification.personalisation == {}
+
+
+@pytest.mark.parametrize('input_value', [
+    None,
+    {}
+])
+def test_notification_personalisation_setter_always_sets_empty_dict(sample_notification, input_value):
+    sample_notification.personalisation = input_value
+
+    assert sample_notification._personalisation == encryption.encrypt({})