Costing activity found, in recent years, in the surviving records of Industrial Revolution business firms has legitimized the claim that the period was a significant precursor of the scientific management movement. This paper reviews the costing practices of a number of British Industrial Revolution iron firms with particular focus on four dominant enterprises (Carron, Cyfarthfa, Darby and Dowlais) for which an extensive volume of business records survives. Evidence of certain mature costing methods, not thought to have pre-dated the 1880s, is detailed and a perspective on iron-industry cost-management practices is provided. These methods are also considered collectively with respect to the general socio-economic environment of the period.