Thoix is situated 15 miles (24 km) southwest of Amiens, on the D100 road. The Parquets river, a small tributary of the river Évoissons, which flows into the Selle, has its source in Thoix and also feeds the castle moat
The village has been known by many names over the centuries: Teoletum, Teoleium, Tois in 1140, Thois in 1212 and Thoys by 1301. The inhabitants are known as Téoduliens.