The COVID-19 pandemic raised concerns regarding increased suicide-related behaviours. We compared characteristics and counts of Emergency Department (ED) presentations for self-harm, an important suicide-related outcome, during versus prior to the pandemic’s first year. We included patients presenting with self-harm to the ED of two trauma centres in Toronto, Canada. Time series models compared intra-pandemic (March 2020-February 2021) presentation counts to predictions from pre-pandemic data. The self-harm proportion of ED presentations was compared between the intra-pandemic period and preceding three years. A retrospective chart review of eligible patients seen from March 2019-February 2021 compared pre- vs. intra-pandemic patient and injury characteristics. While monthly intra-pandemic self-harm counts were largely within expected ranges, the self-harm proportion of total presentations increased. Being widowed (OR=9.46; 95%CI=1.10-81.08), employment/financial stressors (OR=1.65, 95%CI=1.06-2.58), job loss (OR=3.83; 95%CI=1.36-10.76), and chest-stabbing self-harm (OR=2.50; 95%CI=1.16-5.39) were associated with intra-pandemic presentations. Intra-pandemic self-harm was also associated with Intensive Care Unit (ICU) admission (OR=2.18, 95%CI=1.41-3.38). In summary, while the number of self-harm presentations to these trauma centres did not increase during the early pandemic, their proportion was increased. The association of intra-pandemic self-harm with variables indicating medically severe injury, economic stressors, and being widowed may inform future suicide- and self-harm prevention strategies.