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Sulfuryl fluoride (SO2F2) is a synthetic pesticide and a potent greenhouse gas (GHG) that is accumulating in the global atmosphere. SO2F2 has been increasingly used for agricultural and structural fumigation worldwide to replace methyl bromide (CH3Br), which was largely phased out under the Montreal Protocol to protect the ozone layer. Rising emissions of SO2F2 are concerning due to its relatively long atmospheric lifetime and high global warming potential (GWP). However, there is a paucity of information on how emissions of SO2F2 are distributed across the U.S., and there is currently no inventory of SO2F2 emissions for the U.S. or individual states. We provide an atmospheric measurement-based constraint on U.S. SO2F2 emissions using high-precision SO2F2 measurements from the NOAA Global Greenhouse Gas Reference Network (GGGRN) and a geostatistical inverse model. We find that California has the largest SO2F2 emissions among all U.S. states, with the highest emissions from southern coastal California (Los Angeles, Orange, and San Diego counties). Outside of California, only very small and infrequent SO2F2 emissions are detected by our analysis of GGGRN data. We find that California emits 60-85% of U.S. SO F emissions, at a rate of 0.26 (+/-0.10) Gg yr-1 . Furthermore, we estimate that emissions of SO F from California are equal to 5.5-12% of global SO2F2 emissions -- a large contribution from a single state.