This is a working paper, and is currently undergoing peer review. All code and inputs/results data relevant to the analysis is available for download from a separate repository. Enhanced geothermal systems (EGS) are one of a small number of emerging energy technologies with the potential to deliver firm carbon-free electricity at large scale, but are often excluded from macro-scale decarbonization studies due to uncertainties regarding their cost and resource potential. Here we combine empirically-grounded near-term EGS cost estimates with an experience curves framework, by which costs fall as a function of cumulative deployment, to model EGS deployment pathways and impacts on the United States electricity sector from the present day through 2050. We find that by initially exploiting limited high-quality geothermal resources in the Western US, EGS could achieve early commercialization and experience-based cost reductions that enable it to supply up to a fifth of total US electricity generation by 2050 and substantially reduce the cost of decarbonization nationwide. Higher-than-expected initial EGS costs could inhibit early growth and constrain the technology’s long-run potential, though supportive policies can counteract these effects.