Southwest Airlines has announced a further expansion of its operations in Philadelphia with the introduction of a 5x daily service to Boston Logan Airport to begin June 27. Southwest currently serves 17 destinations from Philadelphia, which is US Airways main east coast domestic and international hub. US Airways currently has a market share of 73% in PHL with Southwest 8%.

Over previous years US Airways has focused its Pennsylvania operations in Philadelphia, as the Star Alliance member has scaled down its operations in Pittsburgh which over time has become a focus city for US, rather than a hub with Pittsburgh losing significant US capacity in the process.

US Airways is currently the only carrier providing scheduled operations between PHL and BOS with Delta having discontinued the route during 2009.

Since Southwest entered the Philadelphia market it has set upon an aggressive strategy in targeting US routes. Of Southwest Airlines 17 destinations from PHL, 14 are currently served by US. Two markets namely Houston and Chicago, Southwest operates to secondary city airports. The only city with no US service from PHL is Austin, Texas which US Airways serves from Charlotte and Phoenix.