Today only! Take 75% off the base fare on Spirit flights by entering promo code 75PCT when booking on Spirit.com.
The discount will only apply to the base fare and not to Spirit's online booking fees or taxes so don't expect to see that large of a price drop. Even so, some routes will be discounted heavily.
Travel is valid Mondays, Tuesdays, Wednesdays, Thursdays & Saturdays between January 23 - February 13 and Tuesdays/Wednesdays between February 27 - May 22, 2018. Avoid blackout dates of March 14, 28, April 3 & 4. Certain markets and specific city pairs are also excluded.
Tickets must be booked by 11:59 p.m. ET tonight, January 16, 2018.
There are many more routes available as well. Lowest fares may not be available for the entire travel period.
If you're able to travel ultra light, with just a small personal item, you can get some incredibly cheap flights all across Spirit's network around the USA, Caribbean, and Latin America. Can't travel that light? Checked baggage starts at $30 each way on Spirit so most fliers will likely have to pay at least $60 more round-trip for baggage.
Keep in mind that Spirit is a very basic airline. Do not expect anything more than basic transportation to/from your destination. You'll have to decline any extras to get their lowest price, but if you can take off with just a small rucksack and don't care where you sit, you may be able to save big.