Frontier Airlines, a wholly owned subsidiary of Republic Airways Holdings, launched the four-day fare sale with fares as low as $29 each way. Sale-priced tickets must be purchased by 11:59 p.m. ET on August 4.

Frontier Airlines is giving discounts on flight fares for off-peak travel which is on Tuesday, Wednesday and Saturday for US Travel and Monday to Thursday for Mexico travel. According to the Airlines website, slightly higher fares apply for travelling on other days.

For the U.S. Flights, air fares (plus taxes and fees) will be of each way and it will require a 14-day advance purchase for off-peak travel August 24 through November 17, 2010.

For Mexico Flights Frontier Airlines air fares (plus taxes and fees) will be each way for off-peak travel on Monday through Thursday, based on date of international flight segment from August 24 through November 17, 2010.

According to the Frontier Airlines, for Albuquerque and Aspen $29 tickets will be available. For other destinations in U.S. ticket price will be in between $39 to $79. One-way fares to Mexico include $119 to Puerto Vallarta. For other Mexican destinations ticket will be available from $139 to $149.

Frontier Airlines was founded in 1994, currently flies to 59 destinations throughout Costa Rica, Mexico, and the United States. The vast majority of Frontier flights operate through its hub in Denver.