You cannot stay airside at Heathrow Airport overnight. You can however remain in the public areas and try and sleep (I wouldn't, as I would worry about my belongings getting stolen). There are no sleeping couches, just ordinary seating. If you are worried about visa requirements though, you may be exempt.

Yes, you can stay overnight at London Heathrow Airport (LHR), but the experience depends on whether you stay in a hotel or inside the terminal. In 2026, several terminals have integrated hotels, such as the Sofitel in T5 or the Hilton in T4, which are the most comfortable options. For those on a budget, there are "pod" hotels like YOTEL in Terminal 4. If you plan to sleep in the public areas (landside), you are generally permitted to do so if you have a flight departing the next morning, but it is not recommended for comfort; security may check your documents, and seating is often metallic and designed to discourage long-term lounging. Airside (past security), you can only stay if you are a connecting passenger with a valid boarding pass for the next day, though most terminals "close" certain sections overnight for cleaning. In 2026, travelers from many countries must also ensure they have a valid ETA (Electronic Travel Authorisation) even just to transit.