Carboxymethylcellulose (CMC) was prepared from nine commercial dissolving pulps with different origins, viscosities and S18-values. The rate of the etherification reaction and the final DS were studied with respect to the influence of pulp composition, pulp viscosity and S18-value, and with respect to the sodium hydroxide and sodium monochloro-acetate charges. The possible influence on the final DS-value of the CMC of the washing procedure after the etherification was also investigated.