Summer travel season is about to kick into high gear, and unless you’ve already locked in plans, flight prices are about to jump, according to Thrillist.com.

You might be in luck for procrastinating this year because there are great deals being offered by Frontier Airlines with 2-for-1 deals.

The discount carrier has a bunch of legit 2-for-1 “Friends Fly Free” flight deals on routes all around the country in the next few months, but here’s the case. May 19 is the last day.

The offer, which is available exclusively to members of Frontier’s “Discount Den” deal subscription service, is a follow-up to a similar “Kids Fly Free” promotion the airline ran earlier this year. 

“We’re excited to offer yet another way for our customers to save on flying with our new Friends Fly Free promotion,” said Frontier senior vice president Daniel Shurz, in a press release. “Earlier this year, Frontier began offering Discount Den members our popular Kids Fly Free promotion and both of these offers highlight the foundation of our mission — helping people to travel affordably, more often, and to see new places and connect with loved ones. That’s why we are committed to delivering Low Fares Done Right every day.”

To get in on the deal, you’ll need to be a member of or sign up for the Discount Den (membership is $60 a year), and enter promo code “FLYFREE” when booking (the deal expires at 11:59pm on May 19). 

You’ll be able to nab a buy one get one ticket on a ton of Frontier’s routes between now and August, though you can browse all the specific cities and dates on the official offer page. Keep in mind, though, there are a few blackout dates to keep in mind (around Memorial Day and July 4), and there are restrictions on days of the week you can travel. Also, the offer is only good for two folks traveling together on the same itinerary.