Geologists have long accepted that the Sierra Nevada, California, experienced significant late Cenozoic tectonically induced uplift. A flexural-isostatic model presented here shows, however, that a large fraction of the primary evidence for uplift could be generated by the lithospheric response to coupled erosion of the Sierra Nevada and deposition in the adjacent Central Valley and therefore requires less tectonic forcing than previously believed. The sum of range-wide erosion and the resultant isostatic rock uplift would have lowered Sierra mean elevation by 200 to 1000 meters since 10 million years ago and could also have increased summit elevations during the current period of relief production.