Aiming for rapid and accurate perfusion measurement, background suppressed (BGS) ASL under free breathing is desired. Motion compensation on BGS ASL is challenging due to the lack of anatomical contrast. We investigated the benefit of BGS versus non-BGS ASL, guided by motion compensation based on the ASL-images themselves and additionally acquired fat-images. Registration effect on perfusion weighted signal (PWS) and temporal SNR (tSNR) was evaluated for ASL-image and fat-image based registration, proving increased tSNR and increased PWS robustness, without compromising signal intensity. We conclude that free-breathing BGS renal pCASL with image-based retrospective motion compensation yields better reproducibility than without BGS.