| Airline | Type | Headquarters | IATA Code | Founded |
|---|---|---|---|---|
| American Airlines | Mainline | Fort Worth, Texas | AA | 1926 |
| Delta Air Lines | Mainline | Atlanta, Georgia | DL | 1924 |
| United Airlines | Mainline | Chicago, Illinois | UA | 1926 |
| Southwest Airlines | Low-Cost | Dallas, Texas | WN | 1967 |
| Alaska Airlines | Mainline | SeaTac, Washington | AS | 1932 |
| JetBlue Airways | Low-Cost | Long Island City, New York | B6 | 1998 |
| Spirit Airlines | Ultra Low-Cost | Miramar, Florida | NK | 1983 |
| Frontier Airlines | Ultra Low-Cost | Denver, Colorado | F9 | 1994 |
| Hawaiian Airlines | Mainline | Honolulu, Hawaii | HA | 1929 |
| Allegiant Air | Ultra Low-Cost | Las Vegas, Nevada | G4 | 1997 |
Regional Airlines
| Airline | Type | Headquarters | IATA Code | Founded |
|---|---|---|---|---|
| Envoy Air | Regional | Irving, Texas | MQ | 1998 |
| SkyWest Airlines | Regional | St. George, Utah | OO | 1972 |
| Piedmont Airlines | Regional | Salisbury, Maryland | PT | 1931 |
| Republic Airways | Regional | Indianapolis, Indiana | YX | 1973 |
| Mesa Airlines | Regional | Phoenix, Arizona | YV | 1980 |
| PSA Airlines | Regional | Vandalia, Ohio | OH | 1979 |
| Compass Airlines | Regional | Minneapolis, Minnesota | CP | 2006 |
| GoJet Airlines | Regional | Bridgeton, Missouri | G7 | 2004 |
| Horizon Air | Regional | SeaTac, Washington | QX | 1981 |
| Silver Airways | Regional | Fort Lauderdale, Florida | 3M | 2010 |
