Save up to 35% with Budget From January 5, 2012 through February 15, 2012, you can save up to 35% on qualifying Budget rentals. This offer is valid on all car groups at any participating Budget airport location in the United States. For reservations, book online at southwest.com and enter coupon number U072754 in the Coupon field to receive up to 30% or more off your rental. Discounts greater than 35% may be available in certain markets. Be sure to provide your Rapid Rewards account number at the time of reservation or check in to receive your points. Use this new promotional code to book online & save special fares online with Southwest Airlines. The cheap airline tickets are only available through 15 February 2012. Travel with cheap tickets must take place between 6 January 2012 and 1 March 2012.