The wait is nearly over: Southwest Airlines plans to announce the highly anticipated details of its first-ever South Carolina flights within a week.

The low-fare carrier will disclose the flight times and destinations for Charleston International Airport on Oct. 20. Southwest officials will release its route for Greenville-Spartanburg International Airport the same day.

Officials said last May that the airline would start serving both areas in 2011, later narrowing its takeoff time-frame to the spring of next year.

Southwest recently sent out an invitation to dignitaries to a reception Oct. 20 at Charleston International for "a very special announcement."

No other details have been released, though local tourism officials have been working closely with the airline.

The Dallas-based company's entry into the Lowcountry and Upstate markets is expected to spark fare competition among carriers at both airports, which have some of the highest ticket prices in the nation.

Asked when the details for the Charleston flights would be announced, a Southwest spokeswoman said late last month that it would be "soon. Stay tuned."

The airline previously said it expected to make announcement about its South Carolina itineraries by late fall.

Chicago and Baltimore have been mentioned as two of the carrier's most likely destinations from Charleston.

Aviation experts also expect Southwest to offer nonstop service between Atlanta from the Lowcountry in late 2011 or early 2012, if its recently proposed merger with low-far rival AirTran Airways is approved and completed by then.

Tourism officials estimate that Southwest will save Charleston International travelers $180 million a year in fares. The airline potentially will bring 200,000 new passengers through the local concourses annually.

Reach John McDermott at 937-5572. Reach Allyson Bird at 937-5594.