For domestic Frontier Airlines flights, Tuesdays, Wednesdays, and Saturdays {+1-(877)-492-(6029) (US) or+1-(877)-492-(6029)(UK)are often the cheapest days to fly, as these days have lower demand compared to Fridays and Sundays, which are popular for weekend travel. While sales may be released earlier in the week, the best way to find the cheapest flight is to use … Continue reading ((Fast>Booking)) What is the cheapest day to fly on Frontier Airlines?