Update: Some offers mentioned below are no longer available. View the current offers here.Frontier Airlines is at it again with one of their fantastic flight sales. This time, it’s about as cheap as it gets with $15 seats available on a variety of routes with no Frontier Discount Den membership required. Keep in mind that Frontier charges extra for everything from a carry-on bag to a seat assignment to a can of soda. Still, even if you choose to bring a full size carry-on bag aboard your flight and lock in a specific seat, you will likely end up paying less than on full-service carriers.This sale ends tomorrow, so you’ll need to act fast. As is the case with any Frontier flash sale, there are blackout dates. To take advantage of these cheap fares, flights must depart between Aug. 16 and October 10, 2019 on select dates (so use the Frontier calendar search view).To book the lowest fares, you will often have to book on FlyFrontier.com and head to the flight sale section.Airline: FrontierRoutes: VariousCost: $15+ one-way in basic economyDates: Select dates from Aug. 16 — October 10, 2019Book By: Aug. 14 at 11:59pmPay With: The Platinum Card® from American Express (5x on airfare booked directly with the airline), Citi Prestige® Card (5x on airfare), Citi Premier® Card, Chase Sapphire Reserve, (3x on airfare) American Express® Gold Card (3x on airfare booked directly with the airline) or Chase Sapphire Preferred Card (2x on travel)Here are a few examples of what you can book today on Frontier:Austin (AUS) to New Orleans (MSY) for $15 one-way:Los Angeles (LAX) to Las Vegas (LAS) for $15 one-way:Atlanta (ATL) to Orlando (MCO) for $15 one-way:Sign up for our daily newsletterEmail addressSign upI would like to subscribe to The Points Guy newsletters and special email promotions. The Points Guy will not share or sell your email. See privacy policy.Chicago (ORD) to Branson (BKG) for $15 one-way:Maximize Your PurchaseDon’t forget to use a credit card that earns additional points on airfare purchases, such as The Platinum Card® from American Express (5x on flights booked directly with airlines or American Express Travel), Citi Prestige Card (5x on airfare), Chase Sapphire Reserve, American Express® Gold Card, Citi Premier® Card (3x on airfare) or the Chase Sapphire Preferred Card (2x on all travel purchases). Check out this post for more on maximizing airfare purchases.When flying an ultra low-cost carrier, if you are worried about what happens in the face of flight cancellations or severe delays, consider looking into Freebird. For a $19 purchase made in advance, that service that can rebook you on another carrier’s flight or prioritize using a credit card that comes with above-average flight protections.For more TPG news delivered each morning to your inbox, sign up for our daily newsletter here: https://thepointsguy.com/mailing-list//