The distribution of the bypass flow near the center of a boiling water reactor was calculated with the aid of the COBRA IIIC computer program to determine if boiling of the bypass coolant does occur. A consistant solution for the heat flux traversing the fuel assembly shroud and the bypass flow distribution was obtained for cases with the control rods fully withdrawn and also partially inserted. It was shown that the axial interval between calculated points must be ∼1 cm to obtain a solution that is independent of the spacing between points. Boiling was found to occur in the flow channels that represent the intersection of the narrow gaps between fuel assemblies; however, the average exit enthalpy of the bypass flow was subcooled. Insertion of control rods had a small beneficial effect in reducing the boiling. A 40% increase in the bypass flow rate was found necessary to eliminate boiling completely.