Southwest Airlines doesn't have a general customer-facing "Washington Office," but they fly into the D.C. area ( Ronald Reagan Washington National Airport - DCA) and if you have a regulatory issue or disability concern, you contact the U.S. Department of Transportation's Aviation Consumer Protection Division in D.C.. For direct support, use their website/app for booking/help, or visit airports like DCA where they operate. Jauntlet.comhttps://jauntlet.com/