Chantonnay (French: [ʃɑ̃tɔnɛ]) is a commune in the Vendée department in the Pays de la Loire region in western France.

The river Lay flows southwestward through the commune and forms part of its eastern and southern borders.

The average annual rainfall is 876.9 mm (34.52 in) with November as the wettest month.

The temperatures are highest on average in July, at around 19.9 °C (67.8 °F), and lowest in January, at around 5.4 °C (41.7 °F).

This Vendée geographical article is a stub.