Heathrow Ltd, the airport operator formerly known as BAA, has posted an 11.6% rise in full year profits - amid a rise in airline charges.
Earnings hit £1.26bn from revenue of £2.46bn during 2012 following an average 12.5% hike in airport tariffs since April 2011.
The company said passenger traffic at London's Heathrow, Europe's busiest airport, rose 0.9% to 70 million during the year, while traffic at Stansted fell 3.2% to 17.5 million.
Heathrow is operating at close to capacity and it warned this would limit the UK's ability to trade with emerging economies. There were 471,341 flights during 2012, just below its limit of 480,000 a year.
The group, owned by Spain's Ferrovial, last week announced a £3bn five-year investment plan for Heathrow, which could see passengers facing a rise in ticket prices.
The proposals include the opening of the new Terminal 2 next year, improved check-in and baggage facilities and more customer service training for staff.
The airport needs regulators to approve the plan, which will see the fees it charges airlines to use the airport rise over the period 2014 to 2019.
If approved, the charges would increase from the equivalent of £19.33 per passenger for 2012/13 to as much as £27.30 in 2018/19 - extra costs airlines have opposed.
Heathrow has been at the centre of a debate on the UK's aviation future, with a Government review led by Sir Howard Davies due to report in 2015 on the country's airport capacity amid opposition to the prospect of a third runway.
It is examining whether Heathrow or an alternative site would best serve the UK's needs.