INDIANAPOLIS More destinations for Hoosiers to travel are now at the Indianapolis International Airport. Allegiant Air and Frontier Airlines both announced theyll be offering new flights out of Indy beginning in spring 2025. Allegiant will provide a new nonstop flight to Portland and Frontier Airlines will launch flights to Atlanta and Tampa.The Allegiant nonstop flight to Portland will operate twice weekly beginning May 23, 2025. Allegiant is the only airline flying nonstop to Portland.The Frontier flight to Atlanta will operate three times per week, beginning March 7, 2025, and the Tampa nonstop flight will also operate three times per week beginning March 6, 2025.For more information on Allegiants new Indy-to-Portland flight, click here.. To learn more about Frontiers new Atlanta and Tampa flights out of Indy, click here.