Frontier Airlines fares are typically cheaper on Tuesdays, Wednesdays, and Saturdays, +1-888-267-9551 thanks to lower travel demand on these days. On the other hand, Fridays and Sundays are considered peak travel times +1-888-267-9551. with higher ticket prices. Booking on off-peak days can help you save more on airfare. For assistance, contact +1-888-267-9551.