Lithospheric thickness in the western United States has been found to be thinner than that of the stable continental interior of North America. Explanations for this thin lithosphere range from active tectonics to the presence of partial melt. Importantly, the western U.S. has been used to argue for a relationship between lithospheric thickness and thermotectonic age. Past studies of Sp receiver functions and tomography models in the western U.S. have led to significant improvements in our understanding of mantle structure and related dynamic and tectonic processes, but significant uncertainty remains as the results have yet to be successfully integrated. In our analysis we calculated Sp receiver functions using data from over 1000 broadband stations from more than 50 temporary and permanent networks, ranging from 31N to 43N and 112W to 126W. The average depth of the lithosphere-asthenosphere boundary (LAB) phase across the region in our study is 65.3 km, but absolute depths vary from roughly 30 to 100 km. In this study we take a systemic approach to generating maps of the seismic lithosphere-asthenosphere boundary inferred from Sp receiver functions and compare them to a commonly used map of physiographic provinces and sections, volcanic centers, and the surface wave tomography model of Shen and Ritzwoller (2016) to assess if, and to what extent, our interpretation of the lithosphere-asthenosphere boundary is consistent with these different models and observables. Comparison of our results to the tomography model reveal good agreement between receiver function LAB depth and the absolute depth range between maximum and minimum velocities in the tomography model, suggesting that receiver functions are in fact imaging the lithosphere-asthenosphere boundary. However, little detailed agreement exists between them, likely due to differences in sensitivity. Comparison of LAB depth to our tectonic proxies yields little correlation and we find that the relationship between physiographic boundaries does not appear to extend to variations in lithospheric thickness in the mantle. Preliminary comparisons between petrologic studies and our picks reveal minimal agreement in LAB depth, but we find variation in LAB depth between volcanic centers when compared to non-volcanic areas.