diff --git a/features/basic_replication.feature b/features/basic_replication.feature
index 67b44004..24d0d28f 100644
--- a/features/basic_replication.feature
+++ b/features/basic_replication.feature
@@ -19,6 +19,11 @@ Feature: basic replication
     And I run patronictl.py restart batman postgres1 --force
     Then I receive a response returncode 0
     And "sync" key in DCS has sync_standby=postgres2 after 10 seconds
+    And I sleep for 2 seconds
+    When I issue a GET request to http://127.0.0.1:8010/sync
+    Then I receive a response code 200
+    When I issue a GET request to http://127.0.0.1:8009/async
+    Then I receive a response code 200
 
   Scenario: check the basic failover in synchronous mode
     Given I run patronictl.py pause batman
diff --git a/patroni/api.py b/patroni/api.py
index 4e457765..865de459 100644
--- a/patroni/api.py
+++ b/patroni/api.py
@@ -82,6 +82,14 @@ class RestApiHandler(BaseHTTPRequestHandler):
 
         patroni = self.server.patroni
         cluster = patroni.dcs.cluster
+
+        def is_synchronous():
+            return (cluster.is_synchronous_mode() and cluster.sync
+                    and cluster.sync.sync_standby == patroni.postgresql.name)
+
+        def is_balanceable_replica():
+            return response.get('role') == 'replica' and not patroni.noloadbalance
+
         if cluster:  # dcs available
             if cluster.leader and cluster.leader.name == patroni.postgresql.name:  # is_leader
                 status_code = 200 if 'master' in path else 503
@@ -89,6 +97,10 @@ class RestApiHandler(BaseHTTPRequestHandler):
                 status_code = 503
             elif response['role'] == 'master':  # running as master but without leader lock!!!!
                 status_code = 503
+            elif path in ('/sync', '/synchronous'):
+                status_code = 200 if is_balanceable_replica() and is_synchronous() else 503
+            elif path in ('/async', '/asynchronous'):
+                status_code = 200 if is_balanceable_replica() and not is_synchronous() else 503
             elif response['role'] in path:  # response['role'] != 'master'
                 status_code = 503 if patroni.noloadbalance else 200
             else:
diff --git a/tests/test_api.py b/tests/test_api.py
index 0945711c..1da83d7d 100644
--- a/tests/test_api.py
+++ b/tests/test_api.py
@@ -100,7 +100,7 @@ class MockPatroni(object):
     dcs = Mock()
     tags = {}
     version = '0.00'
-    noloadbalance = Mock(return_value=False)
+    noloadbalance = PropertyMock(return_value=False)
     scheduled_restart = {'schedule': future_restart_time,
                          'postmaster_start_time': postgresql.postmaster_start_time()}
 
@@ -148,6 +148,12 @@ class TestRestApiHandler(unittest.TestCase):
         with patch.object(RestApiHandler, 'get_postgresql_status', Mock(return_value={'role': 'master'})):
             MockRestApiServer(RestApiHandler, 'GET /replica')
         MockRestApiServer(RestApiHandler, 'GET /master')
+        MockPatroni.dcs.cluster.sync.sync_standby = MockPostgresql.name
+        MockPatroni.dcs.cluster.is_synchronous_mode = Mock(return_value=True)
+        with patch.object(RestApiHandler, 'get_postgresql_status', Mock(return_value={'role': 'replica'})):
+            MockRestApiServer(RestApiHandler, 'GET /synchronous')
+        with patch.object(RestApiHandler, 'get_postgresql_status', Mock(return_value={'role': 'replica'})):
+            MockRestApiServer(RestApiHandler, 'GET /asynchronous')
         MockPatroni.dcs.cluster.leader.name = MockPostgresql.name
         MockRestApiServer(RestApiHandler, 'GET /replica')
         MockPatroni.dcs.cluster = None