Heathrow achieved its 31st month of consecutive record growth in May with numbers up by 1.4% to 6.7 million passengers.
The figures emerged ahead of the London hub kicking off a crucial 12-week public consultation on its preferred third runway masterplan on June 18.
Oceania was the best performing region with 10.8% growth as Qantas flew fuller aircraft.
East Asia – up 10.7% – followed closely behind, helped by new routes to China and Japan.
Domestic traffic grew by 2.2% boosted by new Flybe routes to Newquay and Guernsey.
But European Union traffic fell by 2.1% year-on-year and the Middle East fell by 2.1%.
Travellers from the US, Australia, Canada, New Zealand, Singapore, South Korea and Japan started to use eGates at UK airports including Heathrow to cut queues on arrival.
Heathrow chief executive John Holland-Kaye said: “With more countries making use of the eGates, we’re now able to offer passengers from key trading partners a world class experience at the border, showing that Britain is open for business.
“An expanded Heathrow will be key to strengthening these links and we are getting on with delivering our plan as quickly as possible to ensure the UK remains one of the world’s great trading nations as the country leaves the EU.”