The beginning of the 21st Century has produced many significant developments in the history of Philadelphia International Airport. Since 2001, the opening of 2 new terminals and other terminal expansion has more than doubled the size of the Airport terminal complex from 1.4 million to 3.1 million square feet and expanded the number of boarding gates by 94% from 65 to 126. Demand for air travel, spurred by low-fare competition, has increased passenger traffic from 24.9 million in 2000 to 30.7 million in 2009.

The $45 million Terminal E Expansion opened in February 2010. The Expansion features seven new aircraft gates, a 500-seat waiting area, a mini-food court with 3 new concessions, a high bay ceiling filtering in natural lighting and new permanent artwork. The new 9,000 square foot D/E baggage claim with 2 new carousels and new men's and women's restrooms also opened in February 2010.

A 10-year planning process and a thorough 7-year environmental review process culminated in January 2011 with the Federal Aviation Administration (FAA) issuing the Record of Decision (ROD) approving the Airport's Capacity Enhancement Program (CEP). Receipt of this final document enables the Airport to proceed with the next steps required to expand and make critically needed improvements that ensures Philadelphia International Airport is strategically positioned to meet future air service demands, enhance its competitive stature in the global aviation market place and maintain the region's economic vitality. The preferred alternative as selected by the FAA, "Alternative A," provides for a new runway, which will allow independent simultaneous aircraft operations in all weather conditions, to significantly reduce delays. The CEP also calls for two (2) runway extensions, one of which will provide the necessary runway length to accommodate non-stop, long haul flights to reach around the world. New terminals, new cargo facilities and an automated people move system are also included in this alternative.