The Department for Transport says a planned upgrade of Gatwick Airport train station will reduce delays, improve accessibility and provide easier connections for passengers.
£150 million has been earmarked for a project to tackle issues like overcrowding and congestion.
It comes as the number of people using Gatwick Airport station each year has grown by 6 million since 2010.
The development includes doubling the size of the station concourse, adding five new lifts and eight escalators and widening two platforms.
Officials say work to redevelop the station will take around two years to complete - it’s due begin in the spring of next year.
Transport Secretary Chris Grayling said:
"With 46 million people now using Gatwick Airport every year and 20 million coming by train, it is vital that we make the station more accessible and customer friendly for those travelling through it. The UK’s second largest airport has direct rail links to more than 120 destinations and is an important public transport hub.
"We want to see Gatwick Airport’s success continue to flourish and ensure that it is ready for even more passengers in the future. Through this £150 million investment, we will deliver vital upgrades to boost the station’s capacity and provide better, seamless journeys for all."
Stewart Wingate, Chief Executive Officer, Gatwick Airport said:
"Gatwick has been transformed in recent years and the redesigned train station will take the airport’s redevelopment to the next level by providing a seamless transition between the airport and the station, more lifts, escalators and a doubling in the size of the concourse.
"The new station will complement the huge improvements to rail services at the airport, which include new fleets of Gatwick Express and Thameslink trains and services that now leave the airport for London every 3 minutes – as frequently as services on the tube.
"The project is a fantastic example of the public and private sector working together to deliver a world-class transport hub that will comfortably manage the expected growth in air passengers and also encourage people to switch to rail as part of our push to get more people to travel to the airport by public transport."