diff --git a/homeassistant/helpers/entity_registry.py b/homeassistant/helpers/entity_registry.py
index 04d9cc450ba0dab5aa83656cefe960bbf3478823..b222d78b57752d3712fc964162032654fa1d0d96 100644
--- a/homeassistant/helpers/entity_registry.py
+++ b/homeassistant/helpers/entity_registry.py
@@ -109,6 +109,12 @@ class EntityRegistry:
         """Get entity. Create if it doesn't exist."""
         entity_id = self.async_get_entity_id(domain, platform, unique_id)
         if entity_id:
+            entry = self.entities[entity_id]
+            if entry.config_entry_id == config_entry_id:
+                return entry
+
+            self._async_update_entity(
+                entity_id, config_entry_id=config_entry_id)
             return self.entities[entity_id]
 
         entity_id = self.async_generate_entity_id(
@@ -129,6 +135,12 @@ class EntityRegistry:
     @callback
     def async_update_entity(self, entity_id, *, name=_UNDEF):
         """Update properties of an entity."""
+        return self._async_update_entity(entity_id, name=name)
+
+    @callback
+    def _async_update_entity(self, entity_id, *, name=_UNDEF,
+                             config_entry_id=_UNDEF):
+        """Private facing update properties method."""
         old = self.entities[entity_id]
 
         changes = {}
@@ -136,6 +148,10 @@ class EntityRegistry:
         if name is not _UNDEF and name != old.name:
             changes['name'] = name
 
+        if (config_entry_id is not _UNDEF and
+                config_entry_id != old.config_entry_id):
+            changes['config_entry_id'] = config_entry_id
+
         if not changes:
             return old
 
diff --git a/tests/helpers/test_entity_registry.py b/tests/helpers/test_entity_registry.py
index 6808206243f8d1c920a164164971f14e4d54dc7c..5a9efd5c041f7c320f0c23c5e260d822e6fe2fa1 100644
--- a/tests/helpers/test_entity_registry.py
+++ b/tests/helpers/test_entity_registry.py
@@ -107,7 +107,8 @@ def test_loading_saving_data(hass, registry):
     # Ensure same order
     assert list(registry.entities) == list(registry2.entities)
     new_entry1 = registry.async_get_or_create('light', 'hue', '1234')
-    new_entry2 = registry.async_get_or_create('light', 'hue', '5678')
+    new_entry2 = registry.async_get_or_create('light', 'hue', '5678',
+                                              config_entry_id='mock-id')
 
     assert orig_entry1 == new_entry1
     assert orig_entry2 == new_entry2
@@ -191,3 +192,13 @@ def test_async_get_entity_id(registry):
     assert registry.async_get_entity_id(
         'light', 'hue', '1234') == 'light.hue_1234'
     assert registry.async_get_entity_id('light', 'hue', '123') is None
+
+
+async def test_updating_config_entry_id(registry):
+    """Test that we update config entry id in registry."""
+    entry = registry.async_get_or_create(
+        'light', 'hue', '5678', config_entry_id='mock-id-1')
+    entry2 = registry.async_get_or_create(
+        'light', 'hue', '5678', config_entry_id='mock-id-2')
+    assert entry.entity_id == entry2.entity_id
+    assert entry2.config_entry_id == 'mock-id-2'