According to the ITRS predictions, controlling manufacturing yield is going to be a challenging task in future technologies. The effective yield of future FPGA architectures considering configurable logic blocks, switch boxes, connection boxes and routing segments is estimated in this paper. The results show that some degree of redundancy for logic blocks, routing and switch boxes is necessary. However, no more than one spare logic block per cluster, and at most one spare wire is required to obtain a satisfactory effective yield. The results also indicate that it is beneficial to increase logic cluster size of future FPGA architectures for better yield.