Methods and systems for bias control in an optical switch fabric include monitoring optical power at outputs of a plurality of switch elements in an N×N switch fabric that has N inputs, N outputs, and M≥2 stages, each switch element having a respective unique radio frequency tone. A bias control of each of the plurality of switch elements is adjusted. It is determined whether the optical power at the outputs of each respective switch element after bias control adjustment conform more closely to a predetermined criterion relative to the monitored optical power at the outputs of the respective switch element prior to adjustment.