The Airbus A321 will return to Philadelphia on Saturday under the American Airlines banner, following the completion of a merger announced in 2013.
At Hilton Head Island Airport, the merger means that its only commercial airline, US Airways Express, will be rebranded American Eagle starting Saturday. American Eagle is operated by Piedmont Airlines, a subsidiary of American Airlines.
The flights will continue to and from Hilton Head to Charlotte.
Beaufort County airports director Jon Rembold said the Hilton Head airport has undergone the physical changes in preparation for the transition.
"Fliers should see very few changes," he said.
Charlotte is American's second-busiest hub, behind Dallas/Fort Worth.
American has repeatedly said it has no plans to cut the Charlotte hub and has not announced any cuts at Hilton Head's airport.