Cross‐polarization distortion (XPD) due to nonspherical raindrops may be a serious problem for 18.5‐ and 30‐GHz microwave radio communications, but no measured data have yet been published. This paper presents a simple approach for estimating XPD due to rain from the effects of differential attenuation on canted spheroidal raindrops. Values of average raindrop canting angle, θA, are predicted from R. A. Semplak's measurements of differential attenuation taken over a one‐year period, published in 1970. Independent observations of canting angle from two rainstorms, published in 1971 by M. J. Saunders, agree with the predicted values and also indicate values for the senses (positive versus negative) of raindrop canting angles. Estimated values of XPD due to rain are graphically presented for various frequencies, rain rates, and typical path lengths. The paper concludes that the operational limits placed on communications by XPD due to rain are comparable to the limits due to rain attenuation or fading.