BACKGROUND: The current opioid epidemic in the United States has become a public health crisis with an estimated 150 daily deaths and nearly 47,000 opioid-related deaths in the United States in 2017 alone. Sensible prescriber practice changes have been a focus of policymakers to decrease the total number of narcotic pain medications in circulation. In the state of Ohio, opioid prescription limits for acute pain were enacted in August 2017. However, given the association of acute opioid exposure with long-term use and lack of assessment of these policies, there is an unmet need to evaluate the effects of similar legislation in Ohio on postoperative opioid dosing after shoulder arthroplasty. This study evaluates the effects of opioid prescription-limiting legislation in Ohio on postoperative opioid dosing in shoulder arthroplasty and assesses risk factors related to long-term opioid use. METHODS: All patients undergoing primary and revision shoulder arthroplasty over a 5-year period performed by a single surgeon were included. The pre-legislation (PRE) and post-legislation (POST) groups were defined as patients undergoing shoulder arthroplasty before August 31, 2017 and on or after August 31, 2017, respectively. The Ohio Automated Rx Reporting System was queried for controlled-substance prescriptions from 30 days preoperatively to 90 days postoperatively. Patients were designated as opioid tolerant if they had filled an opioid prescription within 30 days of surgery. A binary logistic regression analysis was applied to assess factors related to long-term opioid use. RESULTS: A total of 334 patients were categorized into 2 cohorts: PRE (n = 99) and POST (n = 235). Accounting for legislative effects, we observed significant reductions in cumulative morphine milligram equivalent (MME) dosing in the opioid-naive patients in the 7-day and 30-day postoperative periods (450.0 MMEs in PRE group vs. 210.0 MMEs in POST group, P $<$ .001) and in the opioid-tolerant patients in the 7-day postoperative period (450.0 MMEs in PRE group vs. 250.0 MMEs in POST group, P = .001). Among the opioid-naive patients, the POST group had a significant MME reduction in the 90-day postoperative period relative to the PRE cohort (P $<$ .001). Preoperative opioid tolerance and benzodiazepine tolerance were independent risk factors for increased MME dosing at 90 days postoperatively (P $<$ .001 and P = .02, respectively). CONCLUSION: Opioid prescription-limiting legislation for acute pain in the state of Ohio is associated with a notable reduction in opioid MME dosing in the 90-day postoperative period after shoulder arthroplasty, particularly in opioid-naive patients in the first 30 days postoperatively. Preoperative opioid tolerance is correlated with significantly higher MME dosing postoperatively after shoulder arthroplasty.