diff --git a/lib/ansible/vars/__init__.py b/lib/ansible/vars/__init__.py
index 9cb0108ed6..1405d8736d 100644
--- a/lib/ansible/vars/__init__.py
+++ b/lib/ansible/vars/__init__.py
@@ -362,7 +362,7 @@ class VariableManager:
         variables['playbook_dir'] = loader.get_basedir()
 
         if host:
-            variables['group_names'] = [group.name for group in host.get_groups() if group.name != 'all']
+            variables['group_names'] = sorted([group.name for group in host.get_groups() if group.name != 'all'])
 
             if self._inventory is not None:
                 variables['groups']  = dict()