Heathrow, Stansted and Gatwick have all reported strong growth figures for March.
Both Heathrow and Gatwick reiterated their claims for expansion after growing passenger numbers showed capacity is strained at both airports.
Gatwick announced a 9.2 per cent year-on-year increase with 2.96 million passengers passing through the airport last month.
Heathrow reported a record 5.95 million passengers in March, a 3.4% rise on a year earlier.
Stansted welcomed nearly one million more passengers in the first three months of 2015 over the same period last year and is the fastest growing airport in the UK with 10 consecutive months of double digit growth.
Last week, Gatwick vowed to launch a £20 million fund to support new domestic flights if the airport is allowed to build a second runway.