Multiple non-interfering channels are available in 802.11 and 802.15.4 based wireless networks. Capacity of such channels can be combined to achieve a better performance thus providing a higher quality of service (QoS) than for a single channel network. However, existing routing protocols often are not suited to fully take advantage of these channels. The proposed multi-interface multi-channel routing (MMCR) protocol considers various QoS parameters such as throughput, end-to-end delay, and energy utilization as a single unified cost metric and identifies the route that optimizes the cost metric and balances the traffic among the channels on a per flow basis. Multipoint relay nodes (MPRs) are first selected using available energy and bandwidth and utilized in routing. A novel load balancing scheme is introduced and analytical performance guarantees are demonstrated. Simulation results using the Ns2 show superior performance of the MMCR over the multi-channel optimal link state routing protocol (m-OLSR) in terms of throughput end-to-end delay, and energy efficiency.