Pituitary R2 at 1.5 Tesla has been validated as a sensitive marker of pituitary siderosis and risk of clinical hypogonadism. We cross-validated pituitary R2 measurements at 3T and 1.5T in 26 patients with iron overload syndromes. Pituitary R2 scaled linearly across field strength with a relative enhancement of 42%, consistent with previous liver R2 cross-field validations. When 3T pituitary values were transformed into equivalent 1.5T R2 values, the resulting Z-score estimates were unbiased with native 1.5T R2 estimates. Thus it is not necessary to acquire normative R2 data at 3 Tesla in order to interpret 3T pituitary R2 values.