firebase
diff --git a/firebase_admin/_auth_client.py b/firebase_admin/_auth_client.py
@@ -336,6 +336,8 @@ def update_user(self, uid, **kwargs): # pylint: disable=differing-param-doc
             valid_since: An integer signifying the seconds since the epoch (optional). This field
                 is set by ``revoke_refresh_tokens`` and it is discouraged to set this field
                 directly.
+            providers_to_delete: The list of provider IDs to unlink,
+                eg: 'google.com', 'password', etc.
 
         Returns:
             UserRecord: An updated UserRecord instance for the user.

diff --git a/firebase_admin/_auth_utils.py b/firebase_admin/_auth_utils.py
@@ -266,6 +266,15 @@ def validate_action_type(action_type):
             Valid values are {1}'.format(action_type, ', '.join(VALID_EMAIL_ACTION_TYPES)))
     return action_type
 
+def validate_provider_ids(provider_ids, required=False):
+    if not provider_ids:
+        if required:
+            raise ValueError('Invalid provider IDs. Provider ids should be provided')
+        return []
+    for provider_id in provider_ids:
+        validate_provider_id(provider_id, True)
+    return provider_ids
+
 def build_update_mask(params):
     """Creates an update mask list from the given dictionary."""
     mask = []

diff --git a/firebase_admin/_user_mgt.py b/firebase_admin/_user_mgt.py
@@ -688,7 +688,7 @@ def create_user(self, uid=None, display_name=None, email=None, phone_number=None
 
     def update_user(self, uid, display_name=None, email=None, phone_number=None,
                     photo_url=None, password=None, disabled=None, email_verified=None,
-                    valid_since=None, custom_claims=None):
+                    valid_since=None, custom_claims=None, providers_to_delete=None):
         """Updates an existing user account with the specified properties"""
         payload = {
             'localId': _auth_utils.validate_uid(uid, required=True),
@@ -700,6 +700,7 @@ def update_user(self, uid, display_name=None, email=None, phone_number=None,
         }
 
         remove = []
+        remove_provider = _auth_utils.validate_provider_ids(providers_to_delete)
         if display_name is not None:
             if display_name is DELETE_ATTRIBUTE:
                 remove.append('DISPLAY_NAME')
@@ -715,7 +716,7 @@ def update_user(self, uid, display_name=None, email=None, phone_number=None,
 
         if phone_number is not None:
             if phone_number is DELETE_ATTRIBUTE:
-                payload['deleteProvider'] = ['phone']
+                remove_provider.append('phone')
             else:
                 payload['phoneNumber'] = _auth_utils.validate_phone(phone_number)
 
@@ -726,6 +727,9 @@ def update_user(self, uid, display_name=None, email=None, phone_number=None,
                 custom_claims, dict) else custom_claims
             payload['customAttributes'] = _auth_utils.validate_custom_claims(json_claims)
 
+        if remove_provider:
+            payload['deleteProvider'] = list(set(remove_provider))
+
         payload = {k: v for k, v in payload.items() if v is not None}
         body, http_resp = self._make_request('post', '/accounts:update', json=payload)
         if not body or not body.get('localId'):

diff --git a/integration/test_auth.py b/integration/test_auth.py
@@ -496,6 +496,14 @@ def test_disable_user(new_user_with_params):
     assert user.disabled is True
     assert len(user.provider_data) == 1
 
+def test_remove_provider(new_user_with_provider):
+    provider_ids = [provider.provider_id for provider in new_user_with_provider.provider_data]
+    assert 'google.com' in provider_ids
+    user = auth.update_user(new_user_with_provider, providers_to_delete=['google.com'])
+    assert user.uid == new_user_with_params.uid
+    new_provider_ids = [provider.provider_id for provider in user.provider_data]
+    assert 'google.com' not in new_provider_ids
+
 def test_delete_user():
     user = auth.create_user()
     auth.delete_user(user.uid)

diff --git a/tests/test_user_mgt.py b/tests/test_user_mgt.py
@@ -663,6 +663,23 @@ def test_update_user_valid_since(self, user_mgt_app, arg):
         request = json.loads(recorder[0].body.decode())
         assert request == {'localId': 'testuser', 'validSince': int(arg)}
 
+    @pytest.mark.parametrize('arg', [['phone'], ['google.com', 'phone']])
+    def test_update_user_delete_provider(self, user_mgt_app, arg):
+        user_mgt, recorder = _instrument_user_manager(user_mgt_app, 200, '{"localId":"testuser"}')
+        user_mgt.update_user('testuser', providers_to_delete=arg)
+        request = json.loads(recorder[0].body.decode())
+        assert set(request['deleteProvider']) == set(arg)
+
+    @pytest.mark.parametrize('arg', [[], ['phone'], ['google.com'], ['google.com', 'phone']])
+    def test_update_user_delete_provider_and_phone(self, user_mgt_app, arg):
+        user_mgt, recorder = _instrument_user_manager(user_mgt_app, 200, '{"localId":"testuser"}')
+        user_mgt.update_user('testuser',
+                             providers_to_delete=arg,
+                             phone_number=auth.DELETE_ATTRIBUTE)
+        request = json.loads(recorder[0].body.decode())
+        assert 'phone' in request['deleteProvider']
+        assert len(set(request['deleteProvider'])) == len(request['deleteProvider'])
+        assert set(arg) - set(request['deleteProvider']) == set()
 
 class TestSetCustomUserClaims: