Objective: This study examines the association between community-level marginalization and emergency room (ER) wait time in Ontario.

Methods: Data sources included ER wait time data and Ontario Marginalization Index scores. Linear regression models were used to quantify the association.

Results: A positive association between total marginalization and overall, high-acuity and low-acuity ER wait time was found. Considering specific marginalization dimensions, we found positive associations between residential instability and ER wait time and negative associations between dependency and ER wait time.

Conclusions: Reductions in community-level marginalization may impact ER wait time. Future studies using individual-level data are necessary.