CT coronary angiography (CTA) and non-contrast coronary MRA are established non-invasive methods for anatomical assessment of coronary artery stenosis; however, functional information is limited. Transluminal attenuation gradient (TAG) of CTA predicts a functional significant stenosis. The aim of this study was to access TAG using non-contrast whole heart coronary MRA (MRA TAG) as compared to TAG using CTA (CTA TAG). Preliminary evaluation of MRA TAG provides acceptable prediction of invasive FFR. Further study is required to determine an appropriate prediction of MRA TAG.