The objective of the present study, an extension of a recent one, is to intercompare the utility of the various isothermal three-parameter equations of state (EOSs) of solids, considered viable at different stages in the development of the EOS field, spanning over a period of about a century now. In a recent paper we have compared our isothermal three-parameter equation of state of solids with seven three-parameter isothermal EOSs-five corresponding to the regression curves of V /V 0 on P, and two to those of P on V /V 0 . In this study, we investigate the relative utility of 21, i.e., virtually all, of the viable threeparameter EOSs-for the purposes of smoothing and interpolation of pressurevolume data, and extraction of accurate values of isothermal bulk modulus and its pressure derivative-corresponding to the regression curves of P on V /V 0 . We have applied the EOSs, with no constraint on the parameters, to accurate and model-independent isotherms of nine solids, and assessed the goodness of the fitting accuracy; goodness of the stability of the fit parameters B 0 , B 0 , and B 0 with variation in the pressure/compression ranges; and goodness of the agreement of the fit parameters B 0 and B 0 with experiment. Further, an additional test of goodness of randomization of the data points about the fit curves, quantified in terms of the number of wiggles of the data deviation curves about the fits, is also applied in the present study. The EOSs subjected to these seven tests are the three-parameter extensions of the EOS models formulated by Bridgman (1929), Murnaghan (1937), Birch (1938), Slater (1939, Davis and Gordon (1967), Macdonald (1969), Holzapfel (1991, Poirier and Tarantola (1998), and the so-called 'universal EOS' promoted by Vinet et al (1986). Also included for the inter-comparison purposes are the threeparameter EOSs proposed by Keane (1954), Mao (1970), Thomsen (1970, Huang and Chow (1974), Luban (1983, Kumari and Dass (1990), Hama andSuito (1996), and Bose Roy and Bose Roy (1999), and also the EOS based on a modified Eulerian strain as suggested by Sushil et al (2004). Interestingly, the three-parameter Mie-Gruneisen EOS, built on the