Cheers went up at Ontario International Airport (ONT) when Southwest Airlines announced it will begin daily service to Baltimore/Washington International Thurgood Marshal Airport (BWI) June 5, 2025.

“We could not be happier with the new Southwest service to the greater Washington, D.C., area via BWI, which will be our 26th nonstop destination,” said Alan D. Wapner, president, Ontario international Airport Authority Board of Airport Commissioners. “The addition of this daily nonstop service demonstrates the carrier’s strong confidence in our facilities and amenities, and it is recognition of the increasing demand for air travel through our Southern California gateway.”

The nation’s capital is easily accessible by rail from BWI, which is also a major connecting hub for Southwest.