Heathrow Ltd, the UK airports operator formerly known as BAA, has posted a pre-tax profit of £112 million ($180.3 million) for the nine months to 30 September.
Its year-to-date figure for the first three quarters compares with a pre-tax loss of £147 million during the same period in 2011.
Revenue improved 8.2% to £1.84 billion but operating profit fell 22% to £399 million.
London Heathrow airport's operating profit declined 18.3% to £374 million. Revenue grew 8.9% to £1.66 billion, while passenger numbers were up 0.6% to 53 million.
London Stansted airport saw its operating profit fall 58.2% to £20.2 million, as revenue increased 2.26% to £185 million. Passenger numbers at Stansted dropped 4.6% to 13.5 million.