Heathrow Airport said on Friday it brought in a record 6.5 million passengers in March as people travelled for the Easter bank holiday weekend and half-term.
The airport, which is planning to build a third runway, said the number of passengers marked a 5.5% increase compared to 2017 and its 17th consecutive record month.
Heathrow experienced its busiest ever departures day on March 30 with more than 136,000 passengers jetting off for Easter and the school holidays.
Long-haul emerging destinations were some of the best performers with 12% growth in African markets, a 11% rise in the Middle East and a 7.3% gain in Latin America. That offset a 1.5% decline in the UK.
A vote in summer?
"The booming growth in passenger numbers and cargo, particularly from emerging markets, underpins the urgency to secure Britain's economic future with a third runway at Heathrow - which has now been backed by the cross-party Transport Select Committee,” said chief executive John Holland-Kaye.
MPs are expected to vote on whether to approve Heathrow’s expansion plan in the summer.
The Transport Select Committee said in March that it believed that the runway should go ahead but only after the government addressed concerns about the environmental impact, air quality and noise.
Heathrow is the second busiest airport in the world in international passenger traffic terms after Dubai International, making it prone to flight delays due to capacity problems.