BackgroundNaloxone distributed to people at risk for opioid overdose has been associated with reduced overdose death rates; however, associations of retail pharmacy-distributed naloxone with overdose mortality have not been evaluated. MethodsOur analytic cohort uses retail pharmacy claims data; three health departments’ community distribution data; federal opioid overdose data; and American Community Survey data. Data were analyzed by 3-digit ZIP Code and calendar quarter-year (2016Q1–2018Q4), and weighted by population. We regressed opioid-related overdose mortality on retail-pharmacy and community naloxone distribution, and community-level demographics using a linear model, hypothesizing that areas with high overdose rates would have higher current levels of naloxone distribution but that increasing naloxone distribution from one quarter to the next would be associated with lower overdose. ResultsFrom Q1–2016 to Q4–2018, the unadjusted naloxone distribution rate increased from 97 to 257 kits per 100,000 persons, while the unadjusted opioid overdose mortality rate fell from 8.1 to 7.2 per 100,000 persons. The concurrent level of naloxone distribution (both pharmacy and community) was positively and significantly associated with fatal opioid overdose rates. We did not detect associations between change in naloxone distribution rates and overdose mortality. ConclusionNaloxone distribution volumes were correlated with fatal opioid overdose, suggesting medication was getting to communities where it was needed most. Amid high rates of overdose driven by fentanyl in the drug supply, our findings suggest additional prevention, treatment, and harm reduction interventions are required—and dramatically higher naloxone volumes needed—to reverse the opioid overdose crisis in the US.