U.S. hospital discharges for opioid overdose increased substantially during the past two decades. This brief report describes 90-day readmissions among patients discharged from inpatient stays for opioid overdose. In 2018, survey-weighted analysis of hospital stays in the 2016 Healthcare Cost and Utilization Project National Readmissions Database yielded the national estimated proportion of patients with opioid overdose stays that had all-cause readmissions within ≤90 days. A multivariable logistic regression model assessed index stay factors associated with readmission by type (opioid overdose or not). Number of readmissions per patient was assessed. More than 24% (n=14,351/58,850) of patients with non-fatal index stays for opioid overdose had at least one all-cause readmission ≤90 days of index stay discharge and 3% (n=1,658/58,850) of patients had at least one opioid overdose readmission. Less than 0.2% (n=104/58,850) of patients had more than one readmission for opioid overdose. Patient demographic characteristics (e.g., male, older age), comorbidities diagnosed during the index stay (e.g., drug use disorder, chronic pulmonary disease, psychoses), and other index stay factors (Medicare or Medicaid primary payer, discharge against medical advice) were significantly associated with both opioid overdose and non-opioid overdose readmissions. Nearly 30% of index stays for opioid overdose included heroin, which was significantly associated with opioid overdose readmissions. A quarter of opioid overdose patients have ≤90 days all-cause readmissions, although opioid overdose readmission is uncommon. Effective strategies to reduce readmissions will address substance use disorder as well as comorbid physical and mental health conditions.