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Big sagebrush is a dominant component of many plant communities in the western United States. These ecosystems have been and continue to be reduced in extent and quality due to economic development, invasive species, and climate change, prompting concern about the long-term viability of sagebrush habitat and sagebrush-obligate wildlife species (notably greater sage-grouse). Several processes contribute to future sagebrush viability and geographic distribution, including regeneration. We used a process-based regeneration model for big sagebrush, which simulates potential germination and seedling survival in response to weather and edaphic conditions, to estimate current and future regeneration probabilities. Our results supported expectations of increased probability of weather and soil water conditions that support regeneration in wetter and cooler locations (typically northward and upslope) and decreased probability of regeneration in warmer and drier locations (typically southward and downslope). Our results highlighted that minimum and maximum daily temperatures as well as soil water recharge and summer dry periods are important constraints for big sagebrush regeneration. Climate change pushes soil water dynamics in areas of increasing regeneration probabilities to become more similar to the typical seasonal ecohydrological conditions observed within the current range of big sagebrush ecosystems. By contrast, in areas of declining regeneration probability, increasing winter and spring dryness represent a departure from conditions typically supportive of big sagebrush. Overall, our results are consistent with previous assessments of climate change impacts on overall ecohydrological suitability, i.e., we see consistent changes in areas identified as trailing and leading edges. Decreasing regeneration probability underscores the potential futility of efforts to preserve and/or restore big sagebrush in some areas. Conversely, increasing regeneration probability suggests a growing potential for conflicts in management goals between maintaining existing grasslands by preventing sagebrush expansion versus accepting a shift in plant community composition to sagebrush dominance.