Update: Some offers mentioned below are no longer available. View the current offers here.Again?! Ultra-low-cost carrier Frontier is back with its Friends Fly Free promotion and $19 introductory one-way fares. This latest promo comes less than a week after Frontier offered insanely low $15 one-way fares as part of its new service from Newark International Airport (EWR).Now until the end of Sunday, Sept. 1, Frontier is offering one-way fares from $19 on select routes. The 2-for-1 fares deal ends October 1. Anyone can take advantage of the $19 one-way fares, however, to receive 2-for-1 fares on qualifying routes you must be a member of Frontier’s discount club, Discount Den. Discount Den is an annual membership that allows members to access the least expensive fares and take advantage of Frontier’s ongoing Kids Fly Free program. An annual Discount Den membership costs $60.Both the $19 one-way fares and 2-for-1 fares are only available on select routes. $19 fares are available on travel dates beginning October 6, 2019. Additionally, there are a few blackout dates during which neither offer is available. 2-for-1 fares available with the Friends Fly Free promo feature blackout dates that vary by route. Here are the blackout dates during which $19 fares are not available:Nov. 22 — Dec. 2, 2019Dec. 20 — Jan. 6, 2020If you plan on taking advantage of this promotion, note that Frontier’s fares do not include checked luggage, carry-on bag or seat assignment. The only thing included in fares offered by Frontier is a personal item. All other services and add-ons will only be available for a fee.Airline: FrontierRoutes: Various (see promo)Cost: $19+ one-wayDates: Beginning September 2019Pay 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:Atlanta (ATL) to Tampa (TPA) for $19 one-way + nonstop:Chicago (ORD) to Branson, MO (BKG) for $19 one-way + nonstop: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.Austin (AUS) to New Orleans (MSY) for $19 one-way + nonstop:Raleigh-Durham (RDU) to West Palm Beach (PBI) for $19 one-way + nonstop:Los Angeles (LAX) to Las Vegas (LAS) for $19 one-way + nonstop:2-for-1 from St. Louis (STL) to Denver (DEN) for $34 one-way + nonstop:2-for-1 fare from Newark (EWR) to Phoenix (PHX) for $59 one-way + nonstop: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). For more, check out our post on maximizing airfare purchases.