The functionalization of polymers with phosphorus based reagents is of great interest in the preparation of polymeric materials. In this work we present a straightforward method for the introduction of pendant diethyl phosphate groups into polyglycidol by reaction with diethyl chlorophosphate. The degree of functionalization was controlled by the ratio of the phosphorus reagent to the hydroxyl groups attached to the polyether backbone. Resulting polymers were characterized by 1H, 13C, 31P {1H} NMR spectroscopy, FTIR spectroscopy and SEC analysis. The removal of one and both ethyl groups of the phosphate ester was selectively achieved by reaction with sodium iodide or bromotrimethylsilane, respectively.