The Long-billed Hermit is distributed from southern Mexico through Central America to north-west Colombia. See the distribution map at Birdlife International. Some authorities lump Mexican Hermit P. mexicanus and Ecuadorian Hermit P. baroni with this species.

It is found in the understorey of rainforest, secondary growth and forest edges where it feeds on nectar by trap-lining as well as on arthropods.