Objectives. To examine the impact of North Carolina's 2017 Strengthening Opioid Misuse Prevention (STOP) Act on opioid overdose deaths.Methods. We used quarterly data from the North Carolina Opioid Dashboard to conduct an interrupted time series analysis ranging from 2010 to 2018. Results were stratified by heroin-fentanyl deaths and other opioid deaths.Results. After the STOP Act, there was an initial rate increase of 0.60 opioid deaths per 100 000 population (95% confidence interval [CI] = 0.04, 1.15) and a decrease of 0.42 (95% CI = -0.56, -0.29) every quarter thereafter. Results differed by stratification.Conclusions. Our results suggest that North Carolina's STOP Act was associated with a reduction in opioid deaths in the year following enactment. The changes in opioid overdose death trends coinciding with the STOP Act were similar to outcomes seen with previous opioid policies.Public Health Implications. Future policies designed to reduce the availability of opioids may benefit from encouraging and increasing the availability of evidence-based treatment of opioid use disorder.