Spirit Airlines typically offers itsSpirit Airlines cheapest fares on Tuesdays and Wednesdays. These weekdays are typically less popular for travel, leading to lower demand and therefore lower prices. Additionally, booking flights during off-peak times, such as early in the morning or late at night, can also result in more affordable fares. Flexible travelers who can adjust their schedules to accommodate these less crowded times often enjoy significant savings on Spirit flights. However, it is always advisable to monitor prices and be flexible with travel dates to get the best deals, as prices can fluctuate due to various factors in the airline industry.