Southwest Airlines Co. is a major airline based in the United States and the world's largest low-cost carrier. It is headquartered in Dallas, Texas, and has scheduled service to 121 destinations in the United States and 10 additional countries.

No, Southwest Airlines is primarily a domestic U.S. carrier, though it has significantly expanded its international footprint over the last decade. In 2026, the vast majority (over 90%) of its flights are within the United States, serving over 100 domestic cities. However, Southwest does operate a robust "Short-Haul International" network focusing on the Caribbean, Mexico, and Central America. This includes popular destinations like Cancun, Los Cabos, Montego Bay, Punta Cana, Aruba, and San Jose (Costa Rica). In February 2026, it also added service to St. Thomas in the U.S. Virgin Islands. Notably, Southwest does not fly to Europe, Asia, or South America with its own aircraft. Instead, in early 2026, it launched a series of International Airline Partnerships (with carriers like Turkish Airlines and Philippine Airlines), allowing customers to book global itineraries through the Southwest ecosystem while flying on partner metal, effectively bridging the gap between its domestic roots and global reach.

No, Southwest Airlines is not only international — in fact, it’s primarily a major domestic airline within the United States.

Here’s a breakdown of Southwest’s route network:

1. Primarily a U.S. Domestic Airline

The vast majority of Southwest’s flights are between cities within the United States. It is one of the largest domestic carriers in the U.S. by passenger volume, serving over 100 destinations across the country and its territories.

2. Limited International Service

Southwest does fly to a number of international destinations, but these are relatively few compared to its domestic network. These international flights primarily depart from gateway cities in the U.S. and go to popular vacation spots in: The Caribbean: Aruba, Bahamas, Jamaica, Dominican Republic, Cayman Islands, etc. Mexico: Cancún, Los Cabos, Puerto Vallarta, Mexico City, etc. Central America: Belize, Costa Rica, Honduras. The “International” category also includes U.S. territories like Puerto Rico (which is domestic for customs but often listed as international by airlines).

Key Points to Remember:

• No Long-Haul International: Southwest does not fly to Europe, Asia, South America, or Africa. Its international flights are short to medium-haul from the U.S.
• Point-to-Point Model: Unlike legacy carriers (American, Delta, United) that use hub-and-spoke systems with extensive global alliances, Southwest operates a point-to-point network focused on efficiency and frequent, direct flights within the U.S.
• Famous for Domestic Traits: Southwest is best known in the U.S. for its domestic policies like two free checked bags, open seating (no assigned seats), and lack of change fees.

In summary: Southwest is overwhelmingly a domestic U.S. airline with a supplemental network of international