Abstract The proposed method is general for an ideal multicomponent distillation column with one feed, but with any number of side-cut liquid streams, in addition to the distillate and bottoms. In the derivation, the location and number of pinch points, the analysis of the column, the influence of the presence of the side-cut streams on the characteristic equation and its roots, and the degress of freedom are determined. The calculation procedure together with sample calculation are presented using a hypothetical ten-component mixture to illustrate the numerical evaluation.