In this study, we present new experimental heat capacity data of solid and liquid phase of CsF covering the temperature range from 5 K to 1400 K. The low temperature data were obtained by adiabatic calorimetry and compared with the theoretical heat capacity computed from ab initio harmonic crystal approximation. The absolute entropy at T = 298.15 K determined based on the presented results is 93: 60 J . K-1 . mol(-1). The high temperature heat capacity was measured using a drop calorimeter and the data for the solid phase revealed significant excess properties. The data for the liquid phase were correlated with the molecular dynamic simulation obtaining a good agreement. The recommended molar heat capacity of the CsF solid phase is: C-p,C-m (J . K-1 .mol(-1)) 24.291 + 6.4607 . 10(-2) . (T/K) + 589981 . (T/K)(-2) J . K-1 . mol(-1) and the one of the liquid phase was determined as: C-p,C-m 70.56 J . K-1 . mol(-1). From the calorimetric results the enthalpy of fusion of CsF was determined as: Delta H-fus = 22.1 +/- 2.0 kJ . mol(-1). (C) 2012 Published by Elsevier Ltd.