It comes as the London airport confirmed its summer capacity cap would be removed on 30 October – a move previously welcomed by the travel industry.
Heathrow handled 18 million passengers this summer, but said despite an uptick in demand, total passenger numbers for 2022 will reach between 60-62 million, around 25% fewer than 2019.
"Headwinds of a global economic crisis, war in Ukraine and the impact of Covid-19 mean we are unlikely to return to pre-pandemic demand for a number of years, except at peak times," the airport said.
"Our priority is to build back the airport ecosystem to meet demand at peak times. To do so, businesses across the airport need to recruit and train up to 25,000 security cleared people – a huge logistical challenge."
It hopes the "highly targeted mechanism" it is working on with airlines to align supply and demand on a "small number of peak days" in the lead up to Christmas will "encourage demand into less busy periods".
The airport’s underlying losses have increased to £0.4 billion in the year to date after regulated income failed to cover costs, adding to the £4 billion in the prior two years.
"We have acted responsibly in the face of an uncertain market to protect liquidity and cashflow and reduced gearing. We are not forecasting any dividends this year," the airport added.
Heathrow chief executive John Holland-Kaye said: "We can be proud that everyone at Heathrow pulled together to serve consumers this summer – ensuring 18 million people got away on their journeys, more than any other airport in Europe, with the vast majority experiencing good service.
"We have lifted the summer cap and are working with airlines and their ground handlers to get back to full capacity at peak times as soon as possible."
