On January 1, 2006, Fléron had a total population of 16,088. The total area is 13.72 km2 (5 sq mi) which gives a population density of 1,172 inhabitants per km2. Fléron is east of the city of Liège.
The municipality consists of the following districts: Fléron, Magnée, Retinne, and Romsée.
The reminders of Fort de Fléron are in the center of the village of Fléron.