Objective <p>Emergency departments (EDs) play a critical role in caring for people who use non-prescribed opioids, but ED services for these patients vary widely across Canada. We sought to develop a Canadian checklist for EDs to use in serving people who use non-prescribed opioids based on existing literature, ED professional consensus, and input from people with lived and living experience of drug use.</p> Methods <p>We applied a modified online Delphi approach with two rounds of web-based surveys. We identified participants from a Canada-wide collaborator meeting on the ED initiation of opioid agonist therapy, with additional participants recruited by collaborator suggestion. Initial items for review were generated from a literature review and input from ED clinicians and addiction physicians, and reviewed by people with lived and living experience. In Round 1, participants ranked the relative importance of recommendations within eight domains and suggested additional items. In Round 2, participants rated the retained recommendations and offered further feedback.</p> Results <p>Of 62 participants invited, 30 participated in Round 1 (June–July 2023) and 24 completed both rounds (Round 2: August–November 2023). Participants represented seven Canadian provinces and territories. In Round 1, 37 items were ranked, 15 retained, and 3 new added. In Round 2, 13 of 18 items were rated &gt; 75/100 by at least 75% of participants, spanning six practice domains: ED services offered (<i>n</i> = 3); staffing (<i>n</i> = 2); education and training (<i>n</i> = 2); protocols and policies (<i>n</i> = 2); referrals from the ED (<i>n</i> = 3); and rural and remote services (<i>n</i> = 1).</p> Conclusion <p>A Delphi process generated a 13-item evidence and consensus-informed checklist of ED practices to support caring for people who use non-prescribed opioids. Implementation of the checklist in Canadian EDs has the potential to standardize care and improve outcomes in this patient group.</p>