This article presents a new thermobarometric technique called TWEequ (Thermobarometry With Estimation of EQUilibration state) that uses internally consistent thermodynamic data to assess the equilibration state of mineral assemblages. The method calculates all possible equilibria implied by a given mineral assemblage and uses graphical and statistical methods to determine best estimates of pressure and temperature. The technique is particularly useful for systems where thermodynamic data are well described, allowing for the reconstruction of P–T paths from rocks with disequilibrium textures that pass the local equilibrium test. The method also helps refine thermodynamic properties by identifying incompatible minerals and offering insights into the sensitivity of results to different solution models. The technique is limited by the accuracy of thermodynamic data, especially for solid solutions, but has the potential to improve as these data become more refined. The method facilitates the refinement process by highlighting incompatible minerals, illustrating the sensitivity of results to solution models, and providing a means to select well-equilibrated samples. The article discusses the application of the technique to various mineral systems, including the calc-silicate rock RP13, where it identified potential issues with the activity of annite. The results highlight the importance of accurate thermodynamic data and the need for careful interpretation of thermobarometric results to assess the state of equilibration of samples. The method is particularly useful for identifying systematic errors in calibration and for understanding the equilibrium state of minerals in various geological contexts. The article also discusses the potential for the technique to be used in the study of mineral equilibria and the importance of understanding the equilibrium state of minerals in geological processes.This article presents a new thermobarometric technique called TWEequ (Thermobarometry With Estimation of EQUilibration state) that uses internally consistent thermodynamic data to assess the equilibration state of mineral assemblages. The method calculates all possible equilibria implied by a given mineral assemblage and uses graphical and statistical methods to determine best estimates of pressure and temperature. The technique is particularly useful for systems where thermodynamic data are well described, allowing for the reconstruction of P–T paths from rocks with disequilibrium textures that pass the local equilibrium test. The method also helps refine thermodynamic properties by identifying incompatible minerals and offering insights into the sensitivity of results to different solution models. The technique is limited by the accuracy of thermodynamic data, especially for solid solutions, but has the potential to improve as these data become more refined. The method facilitates the refinement process by highlighting incompatible minerals, illustrating the sensitivity of results to solution models, and providing a means to select well-equilibrated samples. The article discusses the application of the technique to various mineral systems, including the calc-silicate rock RP13, where it identified potential issues with the activity of annite. The results highlight the importance of accurate thermodynamic data and the need for careful interpretation of thermobarometric results to assess the state of equilibration of samples. The method is particularly useful for identifying systematic errors in calibration and for understanding the equilibrium state of minerals in various geological contexts. The article also discusses the potential for the technique to be used in the study of mineral equilibria and the importance of understanding the equilibrium state of minerals in geological processes.