Built in 1825-1824 by  Hargreaves and Hardman the mill ass seen many changes, Irwell mill was one of the earliest to be built in Bacup for the

manufacturing of cotton goods.

 The mill was bought in 1839 by Robert Munn and his brother John who already owned Stacksteads mill. The Munn brothers ran Irwell mill for just over twenty years until it was sold to the Bacup Co otherwise known as the Rossendale Industrial Society.

In 1881 during the great flood of Bacup all the looms in the Weaving shed, the Carding room and Throstle room were all flooded.

In 1911 the company went into receivership and the mill was taken over by Taylor and Hargreaves, who again suffered from flood damage in 1930.

The spinning part of the mill was more commonly known as Hargreaves and Crowther's slipper manufacturers who took over that part of the mill in 1913.

In 1974 the spinning department was taken over by Bacup Shoe Co who used the premises as a warehouse and mill shop. Recently the mill as reopened as the Irwell Mill Medical Practice.