Combined density functional theoretical (DFT) and ab initio methods have been used for the calculation of C-13 NMR chemical shifts of some hydrogen-terminated oligomers of ethylene, propylene, isobutylene, ethylene oxide, vinyl alcohol, and acrylonitrile. The C-13 isotropic chemical shift (delta(iso)) values are calculated with respect to theoretical isotropic shielding constant (sigma(iso)) value of the tetramethylsilane (TMS). The average unsigned error in delta(iso) values of the various oligomers varies between 2 and 5 ppm. The error of ca. 5.22 ppm for acrylonitrile arises mainly due to the cyano carbon. Oligomeric approach has been employed to calculate the delta(iso) values of the corresponding polymers. This approach is validated by the excellent correlation obtained for the linear fits. These calculated delta(iso) values for the polymers are in good agreement with the experimental values.