A method for determining the phase of an electric meter includes: selecting a population of electric meters; selecting a historical time range based at least in part on the selected population of electric meters; selecting an interval period; creating profiles for each electric meter in the selected population of electric meters based on the voltage measurements over one or more interval periods; calculating a correlation coefficient matrix based on the profiles; clustering the selected population of electric meters into a plurality of clusters; and determining a phase of each cluster of the plurality of clusters.