Some 75 million passengers used Heathrow last year, according to figures published by the airport.
The total represents a 2.2% rise on the previous year. Heathrow is hoping to be given permission by the Government to build a third runway, but ministers are carrying out further work to assess the impact this would have on people living near the west London airport.
John Holland-Kaye, chief executive of the airport, said: "It's been an excellent year for Heathrow.
"As we approach our 70th anniversary, our colleagues are delivering the best service we’ve ever achieved to a record number of passengers.
"We’re also making strong progress on our environmental commitments by reducing emissions and noise, and another set of robust financial results underpins our plans to make Heathrow the most sustainable hub airport, and the UK the best connected country in the world.
"I’m confident that this summer the Government will agree with its Airports Commission that expanding Heathrow is the only way to secure Britain’s long-term economic future and meet environmental demands. We stand ready to deliver."
Mr Holland-Kaye also explained why he wants the UK to remain in the European Union ahead of the referendum.
He said: "Membership of the EU has made air travel affordable and convenient, with regular flights to the continent from all parts of Britain - fuelling jobs, exports and economic growth.
"A vote to remain offers the best of both worlds – it secures our place as a powerhouse in the global economy, while remaining in the world’s largest free trade zone.”