Boosted by the arrival of Southwest Airlines, Charleston International Airport is busier than ever.

The Charleston County Aviation Authority reported Thursday that 239,531 passengers traveled through the airport in April. That’s 29 percent more travelers than April 2010 and an all-time record for passenger traffic at the airport, according to Aviation Authority Chairman Chip Limehouse.

The previous record was set at about 230,000 passengers in May 2008 before fuel prices hit record highs that summer and financial markets crashed that fall.

Delta Air Lines served the largest number of travelers in April with 79,181 passengers, about 3 percent more than the same time last year, according to airport officials.

USAirways reported the second-highest number of passengers at 60,514.

Southwest, which started service out of Charleston in mid-March with seven flights a day, served 50,884 passengers in April.

Nearly all carriers at the airport, including American Airlines and Continental Airlines, posted significant increases, according to airport officials.

“That’s really good news,” Airport Director Sue Stevens said. “It’s the Southwest effect.”

Read more in tomorrow’s editions of The Post and Courier.