Update: this popular deal may have sold out. See more deals >
Frontier Airlines has posted discount fares on nine domestic routes, good for travel through summer and early fall.
These are the rules:
– You can fly now through September 21.
– Fly any day of the week.
– Sale fares are one-way only; round-trip purchase not required.
– No advance purchase required.
– Book flights by 11:59pm May 19.