Background Reducing access to lethal means (especially firearms) might prevent suicide, but counseling of at‐risk individuals about this strategy may not be routine. Among emergency department (ED) patients with suicidal ideation or attempts (SI/SA), we sought to describe home firearm access and examine ED provider assessment of access to lethal means. Methods This secondary analysis used data from the Emergency Department Safety Assessment and Follow‐up Evaluation, a three‐phase, eight‐center study of adult ED patients with SI/SA (2010–2013). Research staff surveyed participants about suicide‐related factors (including home firearms) and later reviewed the ED chart (including documented assessment of lethal means access). Results Among 1,358 patients with SI/SA, 11% (95% CI: 10–13%) reported ≥1 firearm at home; rates varied across sites (range: 6–26%) but not over time. On chart review, 50% (95% CI: 47–52%) of patients had documentation of lethal means access assessment. Frequency of documented assessment increased over study phases (40–60%, P < .001) but was not associated with state firearm ownership rates. Among the 337 (25%, 95% CI: 23–27%) patients discharged to home, 55% (95% CI: 49–60%) had no documentation of lethal means assessment; of these, 13% (95% CI: 8–19%; n = 24) actually had ≥1 firearm at home. Among all those reporting ≥1 home firearm to study staff, only half (50%, 95% CI: 42–59%) had provider documentation of assessment of lethal means access. Conclusions Among these ED patients with SI/SA, many did not have documented assessment of home access to lethal means, including patients who were discharged home and had ≥1 firearm at home.