Heathrow Terminal 1, opened by Queen Elizabeth II in May 1968, will say goodbye to its final passengers this evening.
The terminal will close after 47 years with airlines having completed their move to new, modern world class facilities.
The final departure will be a British Airways flight to Hanover.
British Airways (formally BEA) were also the first airline to operate from the terminal in 1968.
Since 2003, Heathrow has invested £11 billion in transforming Heathrow.
Over the last year, the majority of flights have been moved from Terminal 1 to Terminal 2 and as a result, over 60 per cent of Heathrow passengers will now experience new, world class facilities in Terminal 5 and Terminal 2.
The Terminal closure will make way for improved service and way finding around the airport and eventually an extension of the new Terminal 2 will take its place.
If the government supports a third runway at Heathrow then Terminal 2 will be extended farther, providing enough capacity to connect Britain to the world for the 21st century.
Terminal 1 was renowned for being the biggest short-haul terminal of its kind in Western Europe and handled approximately 9 million passengers at full capacity.
In the last few weeks, the terminal has been home to just 17 flights and around 1,700 passengers a day as airlines were phased out of the Terminal.
Heathrow chief executive John Holland Kaye said: “The closure of Terminal 1 marks another important milestone in the transformation of Heathrow.
“Terminal 1 has served Britain well for nearly 50 years, but will soon make way for the expansion of Terminal 2, giving Britain a world class airport that we can all be proud of.”