Passenger numbers at the five UK airports owned by Heathrow Airport Holdings, formerly BAA, increased 2.4% year-on-year to 7.64 million in December.
Total air transport movements across the five gateways fell 2.6% to 61,500.
Among its London airports, Heathrow saw 2% growth in passenger numbers to 5.63 million, while passenger numbers at Stansted rose 4.2% to 1.22 million.
Both Heathrow and Stansted saw falling air transport movements, down by 1.8% and 2% respectively.
Among its other UK airports, Southampton saw passenger numbers decline by 4.3%, while Glasgow and Aberdeen witnessed increases in passenger numbers of 4.3% and 2.9% respectively.
Southampton and Aberdeen saw a fall in air transport movements of 10.2% and 6.7% respectively, while Glasgow posted a rise of 0.3% in December.
Total cargo volumes at BAA's five airports decreased 2.1% to 139,000t, with Heathrow alone accounting for 120,000t.