The surface tension of 1,1,1,3,3-pentafluoropropane (HFC-245fa) and 1,1,1,3,3,3-hexafluoropropane (HFC-236fa) were measured over the temperature range of 254-333 K, using the differential capillary rise method (DCRM) under vapor-liquid equilibrium conditions. The temperature and surface tension uncertainties were estimated to be within +/-10 mK and +/-0.15 mN m(-1), respectively. The present data were used to develop van der Waals-type surface tension correlations for HFC-245fa and HFC-236fa, respectively. (C) 2003 Elsevier B.V. All rights reserved.