Recently, the number of non-linear elements connected to power systems and the non-sinusoidal quantities caused by non-linear loads have been increasing. The influences of the non-sinusoidal quantities on the steady-state voltage stability of power systems have been neglected so far. In this study, a new algorithm presents the effects of the harmonic components caused by non-sinusoidal quantities on voltage stability that are a synthesis of the harmonic power algorithm and the conventional voltage stability analysis. According to this algorithm, the stability analysis was carried out as a numerical application for two different loading conditions in the 11-bus electrical power system. In the first case, the system consists of only linear loads, and in the second case it consists of linear and non-linear loads. Finally, the comparison of harmonic power flow based on voltage stability analysis and conventional voltage stability analysis is examined for the above cases. Copyright (C) 2004 John Wiley Sons, Ltd.