diff --git a/bugsnag/__init__.py b/bugsnag/__init__.py
index 38716463..5a74a852 100644
--- a/bugsnag/__init__.py
+++ b/bugsnag/__init__.py
@@ -13,7 +13,9 @@
                             add_metadata_tab, clear_request_config, notify,
                             auto_notify, before_notify, start_session,
                             auto_notify_exc_info, logger, leave_breadcrumb,
-                            add_on_breadcrumb, remove_on_breadcrumb)
+                            add_on_breadcrumb, remove_on_breadcrumb,
+                            add_feature_flag, add_feature_flags,
+                            clear_feature_flag, clear_feature_flags)
 
 __all__ = ('Client', 'Event', 'Configuration', 'RequestConfiguration',
            'configuration', 'configure', 'configure_request',
@@ -22,4 +24,5 @@
            'auto_notify_exc_info', 'Notification', 'logger',
            'BreadcrumbType', 'Breadcrumb', 'Breadcrumbs',
            'OnBreadcrumbCallback', 'leave_breadcrumb', 'add_on_breadcrumb',
-           'remove_on_breadcrumb', 'FeatureFlag')
+           'remove_on_breadcrumb', 'FeatureFlag', 'add_feature_flag',
+           'add_feature_flags', 'clear_feature_flag', 'clear_feature_flags')
diff --git a/bugsnag/legacy.py b/bugsnag/legacy.py
index b61c7318..df793db4 100644
--- a/bugsnag/legacy.py
+++ b/bugsnag/legacy.py
@@ -1,8 +1,9 @@
-from typing import Dict, Any, Tuple, Type, Optional
+from typing import Dict, Any, Tuple, Type, Optional, Union, List
 import types
 import sys
 
 from bugsnag.breadcrumbs import BreadcrumbType, OnBreadcrumbCallback
+from bugsnag.feature_flags import FeatureFlag
 from bugsnag.configuration import RequestConfiguration
 from bugsnag.client import Client
 
@@ -160,3 +161,22 @@ def _auto_leave_breadcrumb(
     type: BreadcrumbType
 ) -> None:
     default_client._auto_leave_breadcrumb(message, metadata, type)
+
+
+def add_feature_flag(
+    name: Union[str, bytes],
+    variant: Union[None, str, bytes] = None
+) -> None:
+    default_client.add_feature_flag(name, variant)
+
+
+def add_feature_flags(feature_flags: List[FeatureFlag]) -> None:
+    default_client.add_feature_flags(feature_flags)
+
+
+def clear_feature_flag(name: Union[str, bytes]) -> None:
+    default_client.clear_feature_flag(name)
+
+
+def clear_feature_flags() -> None:
+    default_client.clear_feature_flags()
diff --git a/tests/test_client.py b/tests/test_client.py
index b4bd28c8..0caffcfe 100644
--- a/tests/test_client.py
+++ b/tests/test_client.py
@@ -37,6 +37,7 @@ def setUp(self):
                              install_sys_hook=False)
 
         self.client.clear_feature_flags()
+        legacy.clear_feature_flags()
 
     # Initialisation
 
@@ -1564,6 +1565,55 @@ def test_feature_flags_can_be_cleared(self):
 
         assert self.client.feature_flags == []
 
+    def test_feature_flags_can_be_added_individually_with_legacy_client(self):
+        legacy.add_feature_flag('one')
+        legacy.add_feature_flag('two', 'a')
+        legacy.add_feature_flag('three', None)
+
+        assert legacy.default_client.feature_flags == [
+            FeatureFlag('one'),
+            FeatureFlag('two', 'a'),
+            FeatureFlag('three')
+        ]
+
+    def test_feature_flags_can_be_added_in_bulk_with_legacy_client(self):
+        legacy.add_feature_flags([
+            FeatureFlag('a', '1'),
+            FeatureFlag('b'),
+            FeatureFlag('c', '3')
+        ])
+
+        assert legacy.default_client.feature_flags == [
+            FeatureFlag('a', '1'),
+            FeatureFlag('b'),
+            FeatureFlag('c', '3')
+        ]
+
+    def test_feature_flags_can_be_removed_with_legacy_client(self):
+        legacy.add_feature_flags([
+            FeatureFlag('a', '1'),
+            FeatureFlag('b'),
+            FeatureFlag('c', '3')
+        ])
+
+        legacy.clear_feature_flag('b')
+
+        assert legacy.default_client.feature_flags == [
+            FeatureFlag('a', '1'),
+            FeatureFlag('c', '3')
+        ]
+
+    def test_feature_flags_can_be_cleared_with_legacy_client(self):
+        legacy.add_feature_flags([
+            FeatureFlag('a', '1'),
+            FeatureFlag('b'),
+            FeatureFlag('c', '3')
+        ])
+
+        legacy.clear_feature_flags()
+
+        assert legacy.default_client.feature_flags == []
+
     def test_feature_flags_are_included_in_payload(self):
         self.client.add_feature_flags([
             FeatureFlag('a', '1'),