Accurate heats of formation are computed for SFn, SFn+, and SFn-, for n = 1-6. The geometries and vibrational frequencies are determined at the B3LYP level of theory. The energetics are determined at the CCSD(T) level of theory. Extrapolation to the basis set limit is discussed. The temperature dependence of the heat of formation, heat capacity, and entropy are computed for the temperature range 300-4000 K and fit to a polynomial.