Bill Costley (b. 1942) is an American poet and playwright of Scottish and Polish descent. His father was from Glasgow and his mother's family from Grodno, now in Belarus. He has worked as a journalist and librarian.

He lived for a year in Fife, Scotland, organising a words and music event for Fife Writers' Group in support of the Campaign for Nuclear Disarmament (CND). He also contributed to Alan Bold's sporting anthology, The Poetry of Motion.

He was active in the US peace movement.