diff --git a/homeassistant/helpers/selector.py b/homeassistant/helpers/selector.py
index 764f8ed49af..9577381d92b 100644
--- a/homeassistant/helpers/selector.py
+++ b/homeassistant/helpers/selector.py
@@ -277,6 +277,8 @@ class DurationSelector(Selector):
 
     CONFIG_SCHEMA = vol.Schema(
         {
+            # Enable day field in frontend. A selection with `days` set is allowed
+            # even if `enable_day` is not set
             vol.Optional("enable_day"): cv.boolean,
         }
     )
diff --git a/tests/helpers/test_selector.py b/tests/helpers/test_selector.py
index f1d7c83f211..9e68af05487 100644
--- a/tests/helpers/test_selector.py
+++ b/tests/helpers/test_selector.py
@@ -406,12 +406,15 @@ def test_attribute_selector_schema(schema, valid_selections, invalid_selections)
     (
         (
             {},
-            ({"seconds": 10},),
+            (
+                {"seconds": 10},
+                {"days": 10},  # Days is allowed also if `enable_day` is not set
+            ),
             (None, {}),
         ),
         (
             {"enable_day": True},
-            ({"seconds": 10},),
+            ({"seconds": 10}, {"days": 10}),
             (None, {}),
         ),
     ),