According to a source close to Maruping, the 26-year-old has agreed terms on a three-year deal with the Nedbank Cup champions.
Celtic had a one-year option on Maruping's two-year contract, but they will not trigger it.
The former University of Pretoria man made just nine appearances this past season, as coach Veselin Jelusic preferred using Lantshene Phalane and Lucky Baloyi in the centre of the park.
"The deal is as good as done," says the informant.
"Maruping has joined Free State Stars on a three-year deal."
Maruping has been lined up as a direct replacement for Nhlanhla Vilakazi, who will turn out for AmaZulu next season.
Phunya Sele Sele appear to have cash-flow issues, with Jelusic's future in doubt amid reports he is owed money by the club. Celtic boss Max Tshabalala has revealed he is ready to sell the club.