Heathrow is on the verge of losing its position as Europe's busiest airport to Istanbul, new figures from airports group ACI Europe show. In May, just 3,012 more passengers used the west London airport than its Turkish rival, with both recording 7.12 million passengers during the month.
Traffic decline and geopolitical impact
Heathrow suffered a 1.2% decline in passenger numbers from May 2025, while Istanbul enjoyed a 2% year-on-year boost. The airport recently warned that the Iran-US conflict is putting "notable downward pressure on traffic", with its Middle East routes down 25%. Heathrow expects its annual passenger numbers to fall by 1.1% this year compared with 2025.
Capacity constraints and expansion plans
Despite the decline, Heathrow continues to operate its two runways at near-full capacity. The airport's owners are seeking Government permission to build a third runway, which would enable it to accommodate 150 million passengers per year. Some 84.5 million passengers passed through Heathrow's four terminals last year.
Government consultation on expansion
Transport Secretary Heidi Alexander launched a consultation on the renamed Heathrow expansion national policy statement last month, setting out the conditions needed for the project to proceed. Chancellor Rachel Reeves said she was determined to get "spades in the ground" for the third runway in the current Parliament, aiming for completion by 2035.
