We present a new model for the viscosity of molten salts based on the modified Rough-Hard-Sphere (RHS) scheme of DiGuilio and Teja. The model employs the properties of argon to obtain smooth hard-sphere (SHS) viscosity, and the melting points of the molten salts as characteristic parameters. The performance of the model to correlate/predict the viscosities of 38 molten salts is examined in this work. Our results show that the viscosities of these molten salts can be correlated with an AAD (average absolute deviation between calculated and experimental values) of 1.50% using one adjustable parameter for each salt. In addition, values of the adjustable parameter exhibit regular trends with the melting point of the salt for a series of salts with a common anion. (C) 2016 Elsevier B.V. All rights reserved.