Gatwick followed its rival Heathrow by announcing a record August with passengers up by 8.2% to almost 4.4 million.
The busiest month in Gatwick’s history saw an additional 330,300 people use the airport, which used the figures to further push its fight for expansion.
Chief executive Stewart Wingate said: “Building a second runway at Gatwick will promote even greater competition among airports and airlines, delivering reduced fares, better services and more choice for passengers.
“Building a third runway at Heathrow will diminish the choice available to British passengers, making it more expensive to go on holiday, to travel for business and to export goods and services.”
Gatwick handled 906 air traffic movements in a day on its single runway in a single day on August 29 and claimed it as a world first.
San Diego airport – the second-busiest single runway airport in the world – manages on average 500 movements per day, with a record of around 700 in a single day.
North Atlantic routes performed strongly with traffic up by 3.8% as Norwegian Air announced it will double services to New York and Los Angeles from next summer.
There was also a 14% increase to other long haul destinations, which was mainly due to uplift in travel to Dubai. Gatwick’s routes to the UAE, which includes a daily A380 service by Emirates, saw a 13.6% increase in August.
Popular business routes included Geneva, which was up 16.8%, while routes to emerging economies, such as Turkey, also grew with passengers travelling to Istanbul up 34.8% year-on-year.
Wingate said: “Passenger numbers at Gatwick are rapidly increasing and this growth is only expected to continue as we compete for new airlines and open new routes, such as Garuda operating a Gatwick-Jakarta route in September.
“Airports and airlines competing for traffic are delivering tangible benefits for passengers. This is most notably demonstrated by the increasing demand to fly with Norwegian Air on their affordable flights to New York and Los Angeles.
“The popularity of the routes has seen Norwegian Air announce that it will be doubling the frequency of those flights next year.”