List of hub airports

Phoenix Sky Harbor International Airport (PHX)
- Great Lakes Airlines
- Southwest Airlines(Southwest, has a point-to-point carrier, does not have either focus cities or hubs. They do have some cities that have more flights than other cities and this leads to more connecting opportunities. However, this is not the same as focus cities and hubs of other airlines. Source: )
- US Airways

San Francisco International Airport (SFO) - Fortress Hub
- United Airlines - (Dominating Carrier)
- Virgin America
Los Angeles International Airport (LAX)
- Alaska Airlines
- Allegiant Air (Focus City - from May 1, 2009)
- American Airlines (Focus City)
- Delta Air Lines (International Gateway)
- Southwest Airlines (Focus City)(Southwest, has a point-to-point carrier, does not have either focus cities or hubs. They do have some cities that have more flights than other cities and this leads to more connecting opportunities. However, this is not the same as focus cities and hubs of other airlines. Source: )
- United Airlines
Oakland International Airport (OAK)
- Southwest Airlines(Southwest, has a point-to-point carrier, does not have either focus cities or hubs. They do have some cities that have more flights than other cities and this leads to more connecting opportunities. However, this is not the same as focus cities and hubs of other airlines. Source: )

Chicago Midway International Airport (MDW)
- Southwest Airlines(Southwest, has a point-to-point carrier, does not have either focus cities or hubs. They do have some cities that have more flights than other cities and this leads to more connecting opportunities. However, this is not the same as focus cities and hubs of other airlines. Source: )

Baltimore/Washington International Thurgood Marshall Airport (BWI)
- AirTran Airways
- Southwest Airlines(Southwest, has a point-to-point carrier, does not have either focus cities or hubs. They do have some cities that have more flights than other cities and this leads to more connecting opportunities. However, this is not the same as focus cities and hubs of other airlines. Source: )

Las Vegas McCarran International Airport (LAS)
- Allegiant Air
- Southwest Airlines(Southwest, has a point-to-point carrier, does not have either focus cities or hubs. They do have some cities that have more flights than other cities and this leads to more connecting opportunities. However, this is not the same as focus cities and hubs of other airlines. Source: )
- US Airways (Focus City)

Pittsburgh International Airport (PIT)
- US Airways (Small Focus City) (Dominating Carrier)

Dallas-Fort Worth International Airport (DFW) - Fortress Hub
- American Airlines - (Dominating Carrier)
Dallas Love Field (DAL)
- Southwest Airlines(Southwest, has a point-to-point carrier, does not have either focus cities or hubs. They do have some cities that have more flights than other cities and this leads to more connecting opportunities. However, this is not the same as focus cities and hubs of other airlines. Source: )
George Bush Intercontinental Airport (IAH) - Fortress Hub
- Continental Airlines - (Dominating Carrier)
Houston Hobby Airport (HOU)
- Southwest Airlines(Southwest, has a point-to-point carrier, does not have either focus cities or hubs. They do have some cities that have more flights than other cities and this leads to more connecting opportunities. However, this is not the same as focus cities and hubs of other airlines. Source: )