Heathrow Airport does not strictly "close," but it is subject to some of the world's most stringent night flight restrictions to manage noise pollution for the millions of residents living under its flight paths in West London. The UK Government imposes a "Night Quota Period" between 11:30 PM and 6:00 AM, during which only a limited number of take-offs and landings are permitted (roughly 5,800 per year). Additionally, a "Quota Count" system assigns points to aircraft based on their noise levels; louder, older planes are banned during these hours, while quieter, modern aircraft like the Airbus A350 are incentivized. These restrictions provide a crucial "respite" for local communities, allowing them to sleep without the constant roar of engines. In 2026, these rules remain a focal point of the debate over a third runway, as the airport must balance its role as a global economic hub with the physical and mental well-being of its neighbors, only granting "dispensations" for night flights in extreme cases of weather or emergency.