Be sure to click on the "Flight Only" button on Allegiant's site, then choose the from and to cities and your desired dates of travel.
You'll then see a flexible date calendar showing what fares are available on what dates. You may have to click on the calendar's arrows to see months in which the fares we list are available.
Fares may be purchased as one way for 1/2 the round trip fare. Fares may be higher certain days. Occasional lower one way fares may be found. See Allegiant site for all booking details.
Guide to flexible date searches on Allegiant