An all-time record of 60.5 million passengers have travelled through Heathrow so far in 2018.
The airport also recorded robust financial performance, as revenues climbed 2.3 per cent to £2,211 million on the back of higher demand to fly and strong retail spend.
The results will support an additional £555 million of investment into the airport.
Adjusted EBITDA climbed 1.9 per cent to £1,372 million.
John Holland-Kaye, chief executive of Heathrow, said: “With the outcome of Brexit negotiations unknown, strong businesses like Heathrow must stand up to support Britain’s economy.
“We will expand Heathrow to boost Britain’s global trade for decades to come, and we are proud to protect Britain’s small and medium businesses by maintaining our 30-day payment terms for all of our suppliers.
“No matter how small, suppliers should have confidence that they will be paid on-time for their services, and we call on other businesses to follow our lead.”