This article describes the creation of a new urban classification based on the 1891 census of England and Wales. It is the first attempt to use the recently available electronic version of the census (I-CeM) to classify all large towns in late Victorian England and Wales on their economic structure. Where previous scholars were restricted by the form of occupation data contained in the published census reports, I-CeM allows manipulation of the data in order to aggregate urban units and examine their occupational structures in great detail. The classification is then used to compare key socio-economic characteristics of different towns.