diff --git a/synapse/storage/monthly_active_users.py b/synapse/storage/monthly_active_users.py
index c7899d7fd2..e34e16c079 100644
--- a/synapse/storage/monthly_active_users.py
+++ b/synapse/storage/monthly_active_users.py
@@ -192,14 +192,19 @@ class MonthlyActiveUsersStore(SQLBaseStore):
         ))
 
     @defer.inlineCallbacks
-    def populate_monthly_active_users(self, user_id):
+    def populate_monthly_active_users(self, user_id, is_guest=False):
         """Checks on the state of monthly active user limits and optionally
         add the user to the monthly active tables
 
         Args:
             user_id(str): the user_id to query
         """
+
         if self.hs.config.limit_usage_by_mau:
+            # Guests should not be included as part of MAU group
+            if is_guest:
+                return
+
             is_trial = yield self.is_trial_user(user_id)
             if is_trial:
                 # we don't track trial users in the MAU table.
diff --git a/tests/storage/test_monthly_active_users.py b/tests/storage/test_monthly_active_users.py
index 2036287288..cfe0a7c77d 100644
--- a/tests/storage/test_monthly_active_users.py
+++ b/tests/storage/test_monthly_active_users.py
@@ -12,6 +12,9 @@
 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 # See the License for the specific language governing permissions and
 # limitations under the License.
+from mock import Mock
+
+from twisted.internet import defer
 
 from tests.unittest import HomeserverTestCase
 
@@ -23,7 +26,8 @@ class MonthlyActiveUsersTestCase(HomeserverTestCase):
 
         hs = self.setup_test_homeserver()
         self.store = hs.get_datastore()
-
+        hs.config.limit_usage_by_mau = True
+        hs.config.max_mau_value = 50
         # Advance the clock a bit
         reactor.advance(FORTY_DAYS)
 
@@ -73,7 +77,7 @@ class MonthlyActiveUsersTestCase(HomeserverTestCase):
         active_count = self.store.get_monthly_active_count()
         self.assertEquals(self.get_success(active_count), user_num)
 
-        # Test that regalar users are removed from the db
+        # Test that regular users are removed from the db
         ru_count = 2
         self.store.upsert_monthly_active_user("@ru1:server")
         self.store.upsert_monthly_active_user("@ru2:server")
@@ -139,3 +143,39 @@ class MonthlyActiveUsersTestCase(HomeserverTestCase):
 
         count = self.store.get_monthly_active_count()
         self.assertEquals(self.get_success(count), 0)
+
+    def test_populate_monthly_users_is_guest(self):
+        # Test that guest users are not added to mau list
+        self.store.upsert_monthly_active_user = Mock()
+        self.store.populate_monthly_active_users('user_id', True)
+        self.pump()
+        self.store.upsert_monthly_active_user.assert_not_called()
+
+    def test_populate_monthly_users_should_update(self):
+        self.store.upsert_monthly_active_user = Mock()
+
+        self.store.is_trial_user = Mock(
+            return_value=defer.succeed(False)
+        )
+
+        self.store.user_last_seen_monthly_active = Mock(
+            return_value=defer.succeed(None)
+        )
+        self.store.populate_monthly_active_users('user_id')
+        self.pump()
+        self.store.upsert_monthly_active_user.assert_called_once()
+
+    def test_populate_monthly_users_should_not_update(self):
+        self.store.upsert_monthly_active_user = Mock()
+
+        self.store.is_trial_user = Mock(
+            return_value=defer.succeed(False)
+        )
+        self.store.user_last_seen_monthly_active = Mock(
+            return_value=defer.succeed(
+                self.hs.get_clock().time_msec()
+            )
+        )
+        self.store.populate_monthly_active_users('user_id')
+        self.pump()
+        self.store.upsert_monthly_active_user.assert_not_called()