Aboncourt-Gesincourt is a commune in the Haute-Saône department in the region of Bourgogne-Franche-Comté in eastern France.
The population data given in the table and graph below for 1962 and earlier refer to the former commune of Aboncourt. Aboncourt-Gesincourt was established in 1964 by the merger of the former communes Aboncourt and Gesincourt.