But you'll have to act fast — travel must be booked by 11:59 p.m. ET on Thursday.
Frontier Airlines airplane
Credit: Michael Ciaglo/Bloomberg via Getty Images

Spring is in full bloom and so are the deals at Frontier Airlines with up to half-off flights across the country and beyond.

The deal, which is valid through 11:59 pm ET on April 14, is offering 50% off flights throughout Frontier's network, including to popular spring spots like Puerto Rico, Orlando, Charleston, and more, according to the airline. Travelers must book their flight for travel by June 8.

To take advantage of the sale, travelers can book using the code "SAVE50."

The half-off deal can be used for both domestic and international flights on specific days with a round trip purchase required.

Domestic flights are valid on Tuesdays and Wednesdays, with some exceptions like travel to Orlando and Las Vegas, which is valid on Sundays through Wednesdays, and travel to Puerto Rico, which is valid from Sundays through Wednesdays from most locations.

Outbound international travel is available on Sundays through Wednesdays, while travel from an international destination back to the United States is available on Tuesdays through Fridays.

Additionally, several blackout dates apply from April 21 to April 25 and from May 26 to May 31. Travelers must purchase a ticket at least seven days in advance.

The Denver-based carrier flies to more than 90 destinations across the U.S., Mexico, the Caribbean, and Central America, and charges extra for options like seat selection and baggage.

Last month, Frontier reduced the weight limit for checked bags on its flights to a maximum of 40 pounds. Passengers are allowed to bring one personal item free of charge, but must pay for both carry-on bags and checked luggage.

Frontier also offers "Discount Den" memberships for $59.99 per year, which gives members access to things like discounted deals and includes free flights for kids on select routes.

Alison Fox is a contributing writer for Travel Leisure. When she's not in New York City, she likes to spend her time at the beach or exploring new destinations and hopes to visit every country in the world. Follow her adventures on Instagram.