Passengers using Heathrow topped six million last month with a strong December projected.
Thanksgiving and Diwali celebrations helped boost November’s throughput by more than 10% year-on-year to 6.1 million.
Total numbers for the year to November rose by 30% to 72.5 million.
Traffic to North America peaked ahead of Thanksgiving with more than 50,000 passengers flying across the Atlantic from Heathrow on the Friday before the holiday.
Departures to India also proved popular as passengers took 15 daily flights to India from Heathrow to celebrate Diwali.
November also saw Virgin Atlantic operating the first 100% Sustainable Aviation Fuel-powered transatlantic flight.
Toronto, Singapore and Chicago all joined the ‘millionaire’ club in November with more than a million passengers travelling on those routes so far in 2023.
Lisbon, San Francisco and Edinburgh are all in the running to achieve this same milestone, a level set to be reached by more than 20 routes operating at Heathrow by the end of the year.
A strong December is forecast with departure numbers predicted to peak in the week before Christmas Day.
Heathrow chief executive Thomas Woldbye said: “For so many, holidays and cultural festivities are all about spending quality time with friends and family.
“Last month saw passengers travelling to celebrate Thanksgiving and Diwali with their loved ones, and we are making final preparations for the Christmas getaway.
“We need to protect these benefits of aviation in a world without carbon, which the history-making 100% SAF transatlantic flight proved is possible.
“Now we need collaboration between Industry and government who both have critical deliveries, to scale up SAF production to make 100% SAF flights an everyday reality.”