Avançon is located some 10 km south-west of Rethel and 11 km east of Asfeld. Access to the commune is by the D18 road from Acy-Romance in the north-east which passes through the commune to the village near the centre then continues west to Blanzy-la-Salonnaise. The D26 road goes from the village north to Taizy. The D150 goes south-west from the village to Saint-Loup-en-Champagne. The commune is entirely farmland.[3]