Herein, we report the effect of samarium complexation to the modified flavin entity displaying efficient photocatalytic activity toward sulphoxidation reactions. Single crystal X-ray diffraction studies was performed for the structural characterization of the photocatalyst. Spectroscopic and electrochemical studies was undertaken to better understand the nature of the complex when compared to the un-metalated flavin moiety. While the catalytic efficiency was best observed in 20% water in trifluoroethanol using 1 mol% of the catalyst in presence of Blue LED light under oxygen atmosphere. Insignificant product formation was observed with un-metalated flavin moiety. A wide range of sulphides were used to explore the substrate scope. © 2022 Georg Thieme Verlag. All rights reserved.