Molar solution enthalpies of AgNO3, CsNO3, AgCs(NO3)(2) and Ag3Cs(NO3)(4), were measured in pure water at 298.15 K, using different calorimeters. The corresponding molar solution enthalpies at infinite dilution are then used to derive the enthalpies of formation of the AgCs(NO3)(2) and Ag3Cs(NO3)(4) compounds referred to the pure nitrates respectively as -7.34 and -9.33 kJ mol(-1). (C) 2012 Elsevier BM. All rights reserved.