Allegiant Air is offering new flights at BWI. (Courtesy of Allegiant Air)

Allegiant Air, a Nevada-based airline, said Tuesday it will offer new service this spring from Baltimore-Washington International Thurgood Marshall Airport.

Allegiant’s announcement comes as it offers 19 new routes from three airports, including Washington/Baltimore. The other new cities are Destin, Fla., and El Paso, Tex.

The service will include nonstop flights toBWI from Savannah, Ga.; Cincinnati, Ohio; Tulsa, Okla.; Asheville, N.C.; Knoxville, Tenn.; Lexington, Ky. It begins in April, May and June.

Allegiant, based in Las Vegas, runs low-cost flights.