Heathrow expects this summer to be the "busiest on record" after its strongest-ever start to the year, though it faces strike action next month.
The west London hub reported lower revenue and underlying profit though, down 0.7% to £808 million and 8.8% lower to £443 million respectively.
This was despite a 9.5% increase in the number of passengers that flew via Heathrow in the first three months of the year to 18.5 million, driven by increased traffic on business routes and strong demand from North America and East Asia.
For the full year it now forecasts 82.4 million passengers.
Finance chief Javier Echave said: "The summer getaway is expected to be the busiest on record, and we have a robust operating plan in place to keep the airport running smoothly."
Last month refuellers working at the airport warned they would down tools for 72 hours beginning on 4 May as part of industrial action over what the Unite union called “drastic cuts to the terms and conditions of new staff”. The strikes could see planes delayed, disrupted and grounded, Unite warned.
The airport said it has launched a new business strategy focused on efficiency and sustainability, alongside a £1 billion investment in security enhancements and infrastructure upgrades, including new security lanes and a state-of-the-art baggage system.
The airport also criticised current government policies, such as the tourist tax and restrictive travel visas, saying "current government policy is curtailing the UK's growth and competitiveness".