Two distinct approaches pertaining to the chemical structure are applied to predict the specific heat of combustion (DELTAh(c)) of polymers. It has been found that the experimental and calculated values of DELTAh(c) are in good agreement, particularly for polymers of high hydrogen content and low atomic ratio of halogen/carbon. For copolymers, DELTAh(c) is demonstrated to be a weight-average of its component values derived from the corresponding homopolymers. The practical implications of the present findings are discussed.