The development of an equation for Poynting correction, is of paramount importance in the field of modeling and interpretation of phase equilibrium thermodynamics in a wide range of temperatures and pressures /densities for practical applications in chemistry, physical chemistry, geochemistry and industrial technology. The unique previous existing equation for Poynting correction is a simple expression, represented by a product of a constant volume by a pressure difference between wich the correction is applied. [1] proposed an equation based on a semitheoretical expression for the partial molar volume at infinite dilution of volatile aqueous non-electrolyte solute (V 2 0) that considers as variables the density and isothermal compressibility of the solvent, as well as the second cross solvent-solute virial coefficient (12) and the second virial coefficient of pure solvent (11). The mathematical equation is applicable to solutes whose 12 is known or can be estimated, in a temperature range of 273.16 K to 647 K, values of pressure up to 2 kbar and brines with ionic strength equal to 6 m NaCl. The expression provides excellent correlation with experimental data as shown for the H2S-H2O-NaCl system (with maximum deviation of 7%), through a thermodynamic model that uses this formula proposal coupled with the Law of Henry and the Soave-Redlich-Kwong equation of state for modeling the liquidvapor phase equilibria.