In a major expansion of its international partner program, Southwest has today added German airline Condor as its fifth partner carrier, opening up more than 70 destinations across Europe, Africa, Asia, and the Americas.
Since the start of 2025, Southwest has been adding its first-ever international airline partners with the use of so-called interline agreements that allow passengers flying internationally to book a single ticket on both Southwest and the partner airline.
Southwest’s first partner was Icelandair, which launched in February, and after a few months, the airline snagged its second partner in the form of Taiwanese carrier China Airlines in June.
Since then, Southwest has also added fellow Taiwanese carrier Eva Air in August, Philippine Airlines last November, and now the German leisure airline Condor as of December 2025.
Details of the new transatlantic partnership
On Tuesday, Southwest announced that it had struck a deal with Condor, starting up an interline agreement that will open up destinations across Europe, Africa, and Asia for Southwest passengers connecting through Condor’s hub at Frankfurt am Main Airport.
In addition, Condor passengers will have access to destinations across Southwest’s route network in North America. In total, 70 destinations will be part of the interline agreement.
What is an interline agreement?
An interline agreement is an arrangement between two airlines to carry passengers and their baggage on a single ticket, making it easier for passengers to plan, book, and manage journeys that require a connection.
Southwest will connect passengers from Condor flights onto its own route network through six key airports:
- Boston (BOS)
- Las Vegas (LAS)
- Los Angeles (LAX)
- Portland (PDX)
- San Francisco (SFO)
- Seattle (SEA)
Bookings have already opened for connecting itineraries beginning January 19, 2026.
“In Las Vegas alone, we can connect international travelers with the power of our network, offering them more than 270 departures a day and nonstop flights to more than 70 cities,” commented Southwest’s chief operating officer, Andrew Watterson.
“Our airline partnerships showcase the warmth of our People, our operational reliability, and the increasing choice in travel experiences that Southwest now can offer to potential Customers around the world.”
Is Southwest planning for a widebody international future?
Partnerships with international airlines are the first step in Southwest’s eventual move to start its own international services, potentially using widebody jets for the first time in the carrier’s history.
In August, Southwest got the ball rolling for commencing talks with its pilots and flight attendants about an international expansion.
Southwest only started limited international flying in 2014 and, at present, clauses in aircrew contracts only cover international flights to Mexico, Central America, and the Caribbean.
The airline intends to start non-stop flights to Iceland next year, which Southwest can do with its existing Boeing 737 fleet, but chief executive Bob Jordan has revealed that the airline is eyeing a much larger international network across Europe, and Latin America, with even Africa and Asia in consideration as well.
Southwest has already submitted paperwork to the US Department of Transportation (DOT) seeking permission to fly to any country that has a so-called Open Skies agreement with the United States.
The United States has Open Skies agreements with dozens of countries around the world, including all of the European Union and the United Kingdom, as well as India, Japan, Thailand, Australia, and South Korea, to name but a few.
How being “just like any other airline” is paying off
Southwest’s newfound desire to ink deals with international partner airlines and even consider its own long-haul flights stems from its effective takeover by activist investor group Elliott, which assumed control of the airline’s board of directors last October.
Elliott has been determined to make Southwest just like any other airline, ripping up the playbook that Southwest had been playing by for decades.
The jury is still out as to whether Elliott’s gamble will pay off, although Southwest is sounding optimistic that its move into the mainstream is working.
In October, the airline boasted that all of the important metrics were “exceeding its expectations,” and that what Jordan describes as the “most significant transformation in Southwest Airlines’ history” is starting to show positive results.
Bottom line
Even if you ignore everything else that has happened as part of Southwest’s massive transformation program, the move to create interline partnerships with international carriers makes good business sense.
Without these deals, Southwest has had to rely on international passengers going out of their way to book seperate tickets to fly Southwest on a connecting itinerary. In reality, that doesn’t really happen.
