Allegiant Air will charge passengers $35 to carry their own bag on board the plane and stow it in an overhead bin.
The change starts with flights booked on Wednesday, said spokesman Brian Davis. Passengers who pay online when they book travel will pay less, but the price hasn't been set, he said.
Each passenger will be allowed to carry one smaller bag _ such as a purse or briefcase that fits under a seat _ for free.
Allegiant ferries travelers from smaller cities to vacation spots such as Orlando, Fla., and Las Vegas. It touts low fares but, like many airlines, charges extra for services such as early boarding and checking bags.
Allegiant carries less than 4 percent of the traffic of United or Delta.