Southwest Airlines has a present for you on its birthday! Take a trip for as low as $39 one way.

Travelers must book by the end of Thursday for the sale that runs from Aug. 22 to Dec. 16.

The $39 offer is for flights between Oakland and Reno, but other routes are on sale, too. The cheapest flight from Seattle is to Sacramento for $90 one way.

"Cheers to 46 years young," the airline says on its website.

USA TODAY reports most of the sales are valid for travel on Monday through Thursday.