The Acorn Woodpecker is distributed along the Pacific coast of the USA and from south-central USA through Central America to Colombia where it is found in the Andes at between 1,400 and 3,300 metres. See the distribution map at NatureServe. Its habitat is forest borders and lighter woodland particularly, as its name implies, oak Quercus.

It feeds on acorns but also on insects and sap which it extracts from holes that it drills into trees.