Southwest Airlines (LUV) - Get Report is offering steep discounts on international and domestic flights in a flash sale through Thursday night, Fox Business reported.

The sale is for flights from August 22 through December 13, but there are some restrictions and blackout dates. Domestic travel on Fridays and Sundays isn't part of the deal.

A ticket to Atlanta from Boston is just $58, and fare to Las Vegas from Los Angeles costs as little as $42. An international flight to the Cayman Islands from Ft. Lauderdale, Fla., runs as low as $59.

Southwest, which is America's fourth-largest airline by passenger traffic, reported second quarter earnings that beat analysts' expectations. But operating costs weighed on the company, with the stock dipping over 3.5% midday.

Southwest is a holding in Jim Cramer's Action Alerts PLUS Charitable Trust Portfolio. Want to be alerted before Cramer buys or sells LUV? Learn more now.

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