BAA's five UK airports served 9.1 million passengers in June 2012, recording a slight increase of 0.7% when compared with the corresponding month in 2011.
Heathrow airport recorded a 1.6% rise in passenger traffic to more than 6.2 million passengers during the period.
In the first six months of 2012, Heathrow handled 33.6 million passengers, while BAA's airports as a whole handled 47.4 million.
Cargo volume across the group's airports reported a rise of 0.2% when compared with June 2011; the load factor was above 80% and increased by 1%.
Passenger traffic at Stansted airport declined 3.4% in June, while Glasgow's traffic increased 4.5% during the period.
Aberdeen airport reported a 1.3% rise in traffic, despite weather disturbances in June, boosting passenger traffic at BAA's two Scottish airports by 3.5% to 1.02 million.
Heathrow airport's European traffic was affected by weak performances in southern European markets such as Italy, Greece and Portugal, which offset the better performance in Germany, France and Switzerland.
Passenger traffic between Heathrow and Brazil, Russia, India and China performed strongly, with Brazilian traffic rising over 20% during the first half of 2012.
BAA chief executive Colin Matthews said: "Continued growth in passenger numbers are evidence of BAA's consistent performance in a challenging economic climate. But the contrast between the upward trend in passenger numbers to the BRIC economies and the downward trend for those countries most affected by the Eurozone crisis, once again shines the light on the importance to the UK economy of building direct connections with the BRIC countries."
Image: Heathrow airport recorded a 1.6% year-on-year rise in passenger traffic in July 2012. Photo: courtesy of Warren Rohner.