The Colonial Sugar Refining Company was founded on 1 January 1855 by Sir Edward Knox. It was formed in Sydney as a partnership of unlimited liability which took over some of the assets of the Australasian Sugar Company and Robey and Company including sugar stocks and the Brisbane House refinery and distillery. On 1 June 1857 the Colonial Sugar Refining Company shareholders and Victorian business interests formed an associate company – the Victorian Sugar Company – to establish a refinery and distillery in Melbourne. From 1869-70, three large sugar mills were built and operated on the Macleay and Clarence rivers, New South Wales. A new sugar refinery opened in Pyrmont, Sydney, and from 16 February 1878 Pyrmont became the New South Wales refinery. In 1880 Knox handed over the general management of the company to his second son Edward William.

In 1882 the company began sugar production in Fiji with crushing at the Nausori mill. The company also introduced a system of chemical control of processes in its mills. In 1886, Rarawai mill in Fiji , built by CSR for the New Zealand Sugar Company, began crushing. From 1885-88, Dr G Knottman, CSR chemist, developed the POCS formula determining the “pure obtainable cane sugar” in cane. The Colonial Sugar Refining Company and the Victoria Sugar Company were amalgamated in 1887. The company was incorporated as a limited liability company in New South Wales on 1 July 1887 changing its name to the Colonial Sugar Refining Company Limited. The New Farm refinery opened in Brisbane in 1893 and in 1894, CSR’s Lambasa mill in Fiji began crushing. Crushing began at CSR’s Childers mill, near Bundaberg, Queensland, in 1895 and at the Lautoka mill in Fiji in 1903. In 1906 the remaining Kanaka workforce were deported.

In 1915 the Colonial Sugar Refining Company (Fiji and New Zealand) Limited was formed to take over the assets of the company outside Australia. This subsidiary was liquidated in 1923 and the assets returned to CSR Co Limited. I the same year, the Queensland state government signed an agreement with CSR to refine all of that state's sugar production. In 1920 the indentured labour of Indians in Fiji was cancelled on Government decree. CSR introduced a tenant-farming system in Fiji in 1924 as a possible solution to its labour problems. The company bought the Penang mill, Fiji, in 1926.

From around 1939, the Colonial Sugar Refining Company Ltd expanded into manufacturing industrial chemicals through its Industrial Chemicals Division, and building materials as early as 1942 with the construction of a plaster mill in Sydney and manufacturing plasterboard. In 1948 CSR Chemicals Limited was formed, later changing its name to CSR Chemicals Pty Ltd in January 1952. In 1959, CSR acquired an interest in Bradford Insulation. In 1973 the company name changed to CSR Limited. CSR Limited took over Australian Estates Co Ltd in 1975.