In this paper, the benefits of adaptive preselect filtering are investigated by analyzing mote-to-mote throughput in the presence of interference. In a city-wide deployment of a sensor network, of the 150 wireless sensor nodes deployed in our urban test system, five nodes were electrically “lost”. Surprisingly, the limiting factor was not the signal strength, but the neighboring cell towers that caused nearby interference. Therefore, we explored the effect of an adaptive front end to mitigate these nearby interferers. The sensor motes operated at a fixed band, the unlicenced band of 902 to 928 MHz, and did not have the frequency adaptability of future cognitive radios. However, the effect was demonstrative of the potential benefits of adaptive preselect filtering. The measured result shows substantial improvements over the fixed band system by even slight tuning of the bandwidth and/or the center frequency of the preselect filter. Experimentally and numerically, we show that both tuning in the filter bandwidth and/or center frequency can significantly improve the packet reception rate. Guidelines for achieving an optimized filtering technique are given to provide a broad understanding of how the adaptable preselect filtering can be utilized.