A novel concept of thorium once-through fuel cycle for CANDU-type reactors is proposed. The main innovation of the concept is described, including segregation of enriched uranium from thorium to allow separate fuel management routes. Geometry is chosen to enhance leakage of uranium-born neutrons to subcritical thorium parts of the core. Discharged burnup values for thorium and uranium are subjects to optimization regarding uranium savings benefit. Neu-tronic analysis indicated a potential for significant savings in the uranium requirement (∼50%). Fuel cycle cost calculations based on a simple economic model and reasonable set of economic parameters show no economic penalty in realizing fuel utilization improvements.