An airline that hasn't put the first plane on the ground at Charleston International is already expanding its schedule.
Denver-based Frontier Airlines announced Thursday it is adding flights to more destinations than previously indicated at the state's busiest airport.
The low-cost carrier will launch nonstop service three times a week on Sunday, Wednesday and Friday to Trenton, N.J., which is near Philadelphia, starting April 8.
It also will begin twice-weekly flights April 10 to the Texas high-tech mecca of Austin on Tuesday and Friday.
Introductory fares to the two state capitals are as low as $39 each way before they sell out. They must be purchased before midnight Monday and are valid for travel between April 8 and June 13.
Last fall the carrier said it will begin serving the Charleston region Feb. 20 with three flights per week on Tuesday, Thursday and Sunday to the Mile High City and Philadelphia. On May 11, it will tack on Monday and Friday flights to Chicago O'Hare International.
"The idea that we are actually expanding service before our first flight is an unusual event," said Scott Fisher, the airline's senior director of ancillary revenue and loyalty.
The airline decided to announce new routes before it begins offering service because of demand on the original flights announced last fall out of Charleston, he said.
Frontier uses France-based Airbus jets. Those flying out of Charleston will be single-aisle A320 models that seat 180 passengers.
Airport officials said they don't remember a time when a carrier added routes before it touched down in the Lowcountry for the first time.
"It is unprecedented in Charleston for an airline to announce an expansion before the start of its service, but our friends at Frontier Airlines have done just that," said airport CEO Paul Campbell. "It is a vote of confidence that we sincerely appreciate, and the addition of these two new cities will help to ensure an eighth consecutive year of record passenger activity at Charleston International."
Dan Blumenstock, past chairman of the Charleston Area Convention and Visitors Bureau, called the airline's expansion of service "two-way tourism" that's vital to the Charleston region.
Frontier is not the only new airline setting up shop along the ticket counter.
In January, Las Vegas-based Allegiant announced it will begin seasonal, nonstop service in April between Pittsburgh, Cincinnati and Indianapolis on certain days of the week.
Other airlines, including Alaska, Southwest, American and Delta, will add routes throughout the year.
Frontier and Allegiant will be set up at the airline check-in stations next to JetBlue Airways.
The addition of new carriers and more routes from airlines already serving Charleston is expected to push the airport's inbound and outbound passenger count past 4 million this year, a milestone it missed by 12,000 ticket holders last year.
Founded in 1994, Frontier now serves 89 cities.
In addition to the new Charleston legs, Frontier added four cities to its service area. They include Myrtle Beach; Savannah; Birmingham, Ala.; and Branson, Mo. Myrtle Beach service begins May 20. Introductory rates along the Grand Strand are valid for travel between May 16 and Aug. 11.