Techniques for end-to-end network bandwidth optimization using software defined networking are provided. In one embodiment, a computer system can receive information regarding a flow to be admitted to a network, where the flow is associated with a source and a destination. The computer system can further calculate, for each path in a plurality of paths between the source and the destination, a projected utilization of the path in view of the flow. If the projected utilization of the shortest path in the plurality of paths is less than or equal to a target utilization threshold, the computer system can assign the flow to the shortest path. Otherwise, the computer system can select a path in the plurality of paths that comes closest to the target utilization threshold without exceeding the threshold and can assign the flow to that selected path.