Blacko is a village and civil parish in the Pendle district of Lancashire, England. Before local government reorganisation in 1974 the village lay on the border with the West Riding of Yorkshire. The parish has a population of 672. The village is on the old turnpike road from Nelson to Gisburn ( A682). The village enjoys views towards Boulsworth Hill to its southeast, the former cotton town of Nelson, about two miles to its south and Pendle Hill to its west across the valley of Pendle Water.
The parish adjoins the Pendle parishes of Middop, Bracewell and Brogden, Salterforth, Foulridge, Colne, Barrowford, Roughlee Booth and Barley-with-Wheatley Booth. Parts of the parish, west of the village are included in the Forest of Bowland Area of Outstanding Natural Beauty (AONB).