diff --git a/src/app/features/settings/notifications/SystemNotification.tsx b/src/app/features/settings/notifications/SystemNotification.tsx
index 7aafe1db4..894047e46 100644
--- a/src/app/features/settings/notifications/SystemNotification.tsx
+++ b/src/app/features/settings/notifications/SystemNotification.tsx
@@ -381,6 +381,11 @@ export function SystemNotification() {
                 style={selectStyle}
               />
             </Box>
+            {(!quietHoursStart || !quietHoursEnd) && (
+              <Text size="T200" style={{ color: color.Critical.Main }}>
+                Set both a start and end time — quiet hours stay inactive until both are filled in.
+              </Text>
+            )}
           </Box>
         )}
       </SequenceCard>