Most Active Airlines in United States

Key Takeaways

337 airlines fly scheduled routes from the United States. Together they operate 17,901 distinct outgoing routes from the country's airports
Southwest runs the widest network. 1,716 outgoing routes from the United States — about 1.2x the next airline
ORD is the busiest hub. Ranked by the number of outgoing routes departing each airport
Every airline mapped. Explore each carrier's network on the interactive map below

Which airlines are most active in the United States? Using live AirportRoutes data, we ranked every airline by the number of distinct outgoing routes it operates from the United States’s airports — each origin-to-destination pair counted once.

Bar chart of the most active airlines in United States by outgoing routes — The 10 most active airlines in United States, ranked by distinct outgoing routes. Data: AirportRoutes.

The Full Ranking

Full ranking

Most Active Airlines in United States

By distinct outgoing routes operated from the country’s airports.

Airline	Routes	Destinations	Busiest base
1. Southwest	1,716	128	Main hub: DEN
2. SkyWest	1,477	264	Main hub: DEN
3. Delta Air Lines	1,208	237	Main hub: ATL
4. American Airlines	1,187	236	Main hub: DFW
5. United	1,074	228	Main hub: DEN
6. Allegiant Air	895	132	Main hub: SFB
7. Republic	738	104	Main hub: ORD
8. Frontier	665	89	Main hub: DEN
9. Envoy Air	664	189	Main hub: ORD
10. Breeze Airways	504	76	Main hub: RDU
11. PSA Airlines	462	104	Main hub: DCA
12. Spirit	444	82	Main hub: FLL

Each Airline — Where It Flies

Pick an airline and toggle Domestic / Continental / Intercontinental to see where each one flies. Click a dot for details.

1. Southwest

1,716 outgoing routes from 112 airports in the United States to 128 destinations (110 domestic, 18 international). Busiest bases: DEN, MDW, BWI. Top destinations include Denver, Baltimore, Las Vegas, Dallas, Chicago.

2. SkyWest

1,477 outgoing routes from 266 airports in the United States to 264 destinations (243 domestic, 21 international). Busiest bases: DEN, ORD, MSP. Top destinations include Chicago, Denver, Salt Lake City, Dallas-Fort Worth, Los Angeles.

3. Delta Air Lines

1,208 outgoing routes from 154 airports in the United States to 237 destinations (148 domestic, 89 international). Busiest bases: ATL, MSP, JFK. Top destinations include Atlanta, Amsterdam, Minneapolis, Detroit, Salt Lake City.

4. American Airlines

1,187 outgoing routes from 129 airports in the United States to 236 destinations (134 domestic, 102 international). Busiest bases: DFW, MIA, CLT. Top destinations include Dallas-Fort Worth, Charlotte, Miami, Phoenix, Chicago.

5. United

1,074 outgoing routes from 131 airports in the United States to 228 destinations (124 domestic, 104 international). Busiest bases: DEN, EWR, IAH. Top destinations include Denver, Chicago, Houston, Newark, San Francisco.

6. Allegiant Air

895 outgoing routes from 124 airports in the United States to 132 destinations (129 domestic, 3 international). Busiest bases: SFB, PIE, PGD. Top destinations include Orlando, St Petersburg-Clearwater, Phoenix, Las Vegas, Punta Gorda.

7. Republic

738 outgoing routes from 109 airports in the United States to 104 destinations (99 domestic, 5 international). Busiest bases: ORD, LGA, DCA. Top destinations include New York, Chicago, Newark, Washington, Boston.

8. Frontier

665 outgoing routes from 87 airports in the United States to 89 destinations (75 domestic, 14 international). Busiest bases: DEN, ATL, MCO. Top destinations include Atlanta, Denver, Orlando, Dallas-Fort Worth, Chicago.

9. Envoy Air

664 outgoing routes from 173 airports in the United States to 189 destinations (165 domestic, 24 international). Busiest bases: ORD, DFW, MIA. Top destinations include Dallas-Fort Worth, Chicago, Miami, Phoenix, Charlotte.

10. Breeze Airways

504 outgoing routes from 75 airports in the United States to 76 destinations (75 domestic, 1 international). Busiest bases: RDU, MCO, CHS. Top destinations include Orlando, Tampa, Raleigh/Durham, Charleston, Fort Myers.

11. PSA Airlines

462 outgoing routes from 109 airports in the United States to 104 destinations (98 domestic, 6 international). Busiest bases: DCA, CLT, PHL. Top destinations include Charlotte, Washington, Dallas-Fort Worth, Philadelphia, Chicago.

12. Spirit

444 outgoing routes from 56 airports in the United States to 82 destinations (58 domestic, 24 international). Busiest bases: FLL, MCO, LAS. Top destinations include Fort Lauderdale, Orlando, Las Vegas, Newark, Detroit.