Southwest Airlines is having a two-day sale on fares to Las Vegas, the airline's most popular travel destination.

The Dallas-based airline, which shuttles 12 percent of passengers at Philadelphia International Airport, is selling the discounted tickets today through midnight at the end of Wednesday.

The airline said travel must be between Jan. 13 and March 11.

The round-trip fare between Philadelphia and Las Vegas, for instance, will be $149.

For more information and to book tickets, go to http://southwest.com/lasvegas/.

Company shares were trading for $8.23, up 18 cents (2.24 percent) early this afternoon.