Southwest 40 Years Anniversary: Select Flights from $40 Fares One-way

Fares do not include federal excise tax of $3.70 per takeoff and landing, airport-assessed passenger facility charges (PFC) of up to $9, and government-imposed September 11th Security Fee of up to $5 one-way.
Purchase by June 23, 2011, 11:59 pm Pacific Time.
Travel August 23 through November 16, 2011.
Blackout Dates Apply: September 1, September 5, September 6 and October 10, 2011
Travel valid every day except Fridays & Sundays.