Make your first trip of 2018 an affordable one with the airline's last sale of the year.

nassau bahamas
Credit: Laurie Chamberlain/Getty Images

Southwest Airlines is having its last sale of the year, giving you a final chance to grab flights for your 2018 getaway at a fraction of the price.

The airline is offering deals on both domestic and international flights, with trips across the U.S. starting at $49 one-way.

If you're looking to escape the cold, the airline also has deals to sun-soaked destinations like Nassau, Providenciales, and Belize City starting at just $69 one-way from Fort Lauderdale.

Fort Lauderdale travelers can also fly to San Juan, Puerto Rico and to Punta Cana in the Dominican Republic for just $109 one-way and $132 one-way, while Chicago travelers will find flights to Punta Cana that start at $209 one-way.

There are also affordable flights to several popular Mexican beach destinations like Cabo and Cancun, with flights starting at $154 one-way to Cabo and $177 one-way to Cancun from Denver. If you're looking for a calmer Mexican getaway, you can also head to Puerto Vallarta, where you'll find an array of white sand beaches, tropical jungles and vibrant fish markets.

Flights to Puerto Vallarta start at $117 one-way from Los Angeles and at $154 one-way from Houston.

Travelers heading out of Houston will also find flights to Belize City starting at $128 one-way, and flights to Montego Bay for $208 one-way.

The sale runs through 11:59 p.m. on Dec. 28, with domestic deals available for travel between Jan. 1 and May 23 of 2018. Meanwhile, you can book international flights between Jan. 9 and March 1 of next year, or between April 3 and May 18, 2018.

Passengers planning to fly with the airline next year will also want to keep in mind that Southwest will be one of several airlines banning certain types of smart luggage on flights starting in January due to safety concerns over batteries causing potential fires.

To fly with the airline, you’ll want to make sure your smart luggage has a removable battery.