Frontier Airlines said Monday it will add flights from Denver to Chicago, Dallas/Fort Worth, New York and Sacramento, Calif. starting this spring.

The new flights are now available for purchase through Sept. 10.

Frontier will add a fifth flight to Midway in Chicago on May 16, a sixth flight to Dallas/Fort Worth International Airport on May 13, a third flight to LaGuardia in New York on March 13 and a fourth flight to Sacramento International on April 18.

Frontier also announced it will resume its nonstop seasonal summer service between Denver and Fairbanks, Alaska on May 13. Frontier Airlines is a subsidiary of Republic Airways Holdings Inc.