Several major US airlines including Delta, United, US Airways and Virgin America are now offering incredibly cheap airfares on many of their short flights nationwide.

Airline tickets can be purchased for as low as $39-$69 for one-way flights. The cheapest flights are on Tuesdays, Wednesdays or Saturdays, traditionally the least expensive days to fly on flights within the US. These cheap airfares will last through June 8, 2011.

A 21-day advanced purchase is required so the best bargains can be found for travel dates during late March, April and May. However, booking earlier will offer the best choices of flight times as well as the cheapest airfares.

For example, on the east coast, a one-way flight from Boston to Baltimore is only $48 ($117 round trip) on Jet Blue, Continental, Air Tran, and United. A flight from Philadelphia to Providence, Rhode Island, is only $69 ($159 round trip) on US Airways.

Also from US Airways, a flight from Los Angeles to Las Vegas can be had for as low as $39 one way ($79 round trip), and a one-way flight from Phoenix to San Diego is a mere $49 ($119 round trip).

It is important to note that these cheap airfares may not be available for travel dates around Easter, which is April 24 this year, due to the increased demand for flight tickets during holiday times.