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Groundwater inputs to streams, or baseflow, can potentially modulate discharge response to climate extremes, thereby protecting ecosystem health and water supply to downstream users.� Baseflow also serves as a metric of watershed support for groundwater dependent ecosystems; such as springs, mountain meadows and riparian zones, that sustain much of the ecologic biodiversity in the Great Basin.� Large portions of the Great Basin lack a robust stream and meteorological station network making it difficult to assess how sensitive baseflow is to shifts in climate. To address data scarcity we applied a nested-multiple regression approach to nearly 1500 HUC12-sized, perennial watersheds across seven sub-regions in the Great Basin: Central, Eastern Humboldt, Lava Plains, Lahontan, South East Idaho and Utah. Baseflow was calculated using a low pass, automated filter to both active and inactive stream gauges that contained at least 10 years of daily discharge data and were coincident with selected watersheds (n = 34). Monthly historical climate for water years 1896 to 2015 was obtained from the Parameter-elevation Regression on Independent Slopes Model (PRISM), aggregated by water year and processed for watershed mean values based on total and seasonal precipitation and associated mean daily temperatures.� Climate variables were regressed against baseflow over each observed streamflow period of record, and these climate coefficients were then modeled as functions of watershed characteristics defining shape, topography, stream-network configuration and geology.� The subsequent approach allows baseflow to be calculated solely as a function of PRISM and watershed characteristics and is thereby transferable to ungauged basins. We review baseflow as a function of total annual flow over the historic record and present individual sub-regional models of the Great Basin that allow a comparison of physical attributes that promote baseflow resilience to changes in precipitation and temperature.