In this paper we examine the propagation of electromagnetic waves through electroweak textures and W-strings. The photon is associated with a negative mass squared term as a consequence of its coupling to the intermediate vector bosons from which the electroweak defect is constructed. The photon pseudo-mass depends on the polarization of the photon and results in electroweak defects exhibiting birefringent properties. We calculate the effective refractive index and birefringence length scale. The cosmological implications of birefringent electroweak defects are discussed.