U.S. ULCC Frontier Airlines has unveiled a slew of routes commencing in May, with a focus on connecting smaller airports to larger markets.

The carrier will open four routes from Hartsfield-Jackson Atlanta International Airport (ATL) to mid-size markets. All will be operated 3X-weekly and commence May 16 and 17, when flights from ATL begin to Grand Rapids, Michigan; Islip and Syracuse, New York; and Norfolk, Virginia.

On those same dates, Frontier will open service from Chicago O’Hare International Airport to three destinations: Nashville, Tennessee, operating 3X-weekly; Portland, Maine, flown 3X-weekly; and Houston Bush Intercontinental Airport (IAH), served 4X-weekly.

From May 17, the carrier will also start 4X-weekly flights between IAH and Ontario International Airport (ONT) in California. Additionally, Frontier the same week will start daily service between ONT and Seattle and 4X-weekly flights between ONT and El Paso International Airport (ELP) in Texas. It will also commence 3X-weekly flights between ELP and San Diego.

From Missoula, Montana, Frontier will open 4X-weekly service to the carrier's Denver base on May 2 and 2X-weekly flights to Phoenix on May 3.

From New Orleans, the airline will kick off 3X-weekly service to both Indianapolis and Columbus, Ohio, starting May 21 and 22, respectively.

From Orlando, Frontier will open 1X-weekly service to St. Croix in the Caribbean from May 25. Finally, the carrier will start 3X-weekly service between Portland, Oregon, and Salt Lake City, Utah, from May 16.

“We are excited to yet again expand our route map with a focus on underserved and overpriced markets as we head into spring,” says Josh Flyr, Frontier vice president for network and operations design.