The calculated vertical section of the Cu–In–Pb system at xCu/xPb=1. •Thermodynamic modeling of the system Cu–In–Pb.•Calculation of four vertical sections and two isothermal sections.•Calculated liquidus surface projection. Phase equilibria in the Cu–In–Pb system are calculated using a thermodynamic modeling approach. The thermodynamic model parameters for the constituent binaries Cu–In, Cu–Pb and In–Pb are taken from earlier assessments. Thermodynamic description of the ternary liquid phase is obtained based on the phase equilibria data available in literature for the xIn=0.75 vertical section of the Cu–In–Pb system. The liquidus surface projection, isothermal sections at 373 and 573K, as well as vertical sections xCu/xPb=1, xIn=0.75, xIn=0.5, and xIn=0.25 are calculated.