Abstract This paper presents an analytical method for obtaining the transient overvoltage response of large multiwinding power transformers. The windings of the transformer are divided into a finite number of segments and represented in the form of an electrical network containing the self and mutual inductances, series, ground and interwinding capacitances. A mathematical model representing the above network is analysed to calculate the eigenvalues and eigenvectors. Based on this, the temporal and spatial variations of voltage in the windings are computed when subjected to either a unit step or any surge voltage of given waveshape. For various types of transformers the results have been computed and compared with measured values.