A method for determining a location of a phase-to-phase fault on a three-phase electric line of an electric network, the method comprising: monitoring current and voltage quantities of the three-phase electric line at a measuring point; determining, after a phase-to-phase fault occurs on the three-phase electric line, a phase-to-phase fault loop reactance and an initial estimate of a distance between the measuring point and the point of fault on the basis of current and voltage quantities monitored during the phase-to-phase fault, characterized in that the method comprises: determining one or more sets of phase-to-phase fault loop reactance unbalance correction factors on the basis of values of current and voltage quantities monitored during one or more three-phase faults, respectively, each set of correction factors corresponding to a distance between the measuring point and a point of fault at which the respective three-phase fault occurs on the three-phase electric line, wherein the reactance unbalance correction factor for a phase-to-phase fault loop is a ratio of a three-phase fault loop reactance to the phase-to-phase fault loop reactance of the phase-to-phase fault loop in question; determining a phase-to-phase fault loop reactance unbalance correction factor to be used on the basis of the determined one or more sets of phase-to-phase fault loop reactance unbalance correction factors and the initial estimate of the distance between the measuring point and the point of fault; correcting the determined phase-to-phase fault loop reactance with the determined phase-to-phase fault loop reactance unbalance correction factor to be used by multiplying the determined phase-to-phase fault loop reactance with the determined phase-to-phase fault loop reactance unbalance correction factor to be used; and determining a corrected estimate of the distance between the measuring point and the point of fault on the basis of the corrected phase-to-phase fault loop reactance. monitoring current and voltage quantities of the three-phase electric line at a measuring point; determining, after a phase-to-phase fault occurs on the three-phase electric line, a phase-to-phase fault loop reactance and an initial estimate of a distance between the measuring point and the point of fault on the basis of current and voltage quantities monitored during the phase-to-phase fault, characterized in that the method comprises: determining one or more sets of phase-to-phase fault loop reactance unbalance correction factors on the basis of values of current and voltage quantities monitored during one or more three-phase faults, respectively, each set of correction factors corresponding to a distance between the measuring point and a point of fault at which the respective three-phase fault occurs on the three-phase electric line, wherein the reactance unbalance correction factor for a phase-to-phase fault loop is a ratio of a three-phase fault loop reactance to the phase-to-phase fault loop reactance of the phase-to-phase fault loop in question; determining a phase-to-phase fault loop reactance unbalance correction factor to be used on the basis of the determined one or more sets of phase-to-phase fault loop reactance unbalance correction factors and the initial estimate of the distance between the measuring point and the point of fault; correcting the determined phase-to-phase fault loop reactance with the determined phase-to-phase fault loop reactance unbalance correction factor to be used by multiplying the determined phase-to-phase fault loop reactance with the determined phase-to-phase fault loop reactance unbalance correction factor to be used; and determining a corrected estimate of the distance between the measuring point and the point of fault on the basis of the corrected phase-to-phase fault loop reactance. determining one or more sets of phase-to-phase fault loop reactance unbalance correction factors on the basis of values of current and voltage quantities monitored during one or more three-phase faults, respectively, each set of correction factors corresponding to a distance between the measuring point and a point of fault at which the respective three-phase fault occurs on the three-phase electric line, wherein the reactance unbalance correction factor for a phase-to-phase fault loop is a ratio of a three-phase fault loop reactance to the phase-to-phase fault loop reactance of the phase-to-phase fault loop in question; determining a phase-to-phase fault loop reactance unbalance correction factor to be used on the basis of the determined one or more sets of phase-to-phase fault loop reactance unbalance correction factors and the initial estimate of the distance between the measuring point and the point of fault; correcting the determined phase-to-phase fault loop reactance with the determined phase-to-phase fault loop reactance unbalance correction factor to be used by multiplying the determined phase-to-phase fault loop reactance with the determined phase-to-phase fault loop reactance unbalance correction factor to be used; and determining a corrected estimate of the distance between the measuring point and the point of fault on the basis of the corrected phase-to-phase fault loop reactance.