BACKGROUND AND OBJECTIVES: Increasing suicide rates and emergency department (ED) mental abstract health visits reflect deteriorating mental health among American youth. This population-based study analyzes trends in ED visits for suicidal ideation (SI) before and during the coronavirus disease 2019 (COVID-19) pandemic. METHODS: We analyzed Illinois hospital administrative data for ED visits coded for SI from January 2016 to June 2021 for youth aged 5 to 19 years. We characterized trends in patient sociodemographic and clinical characteristics, comparing three equal 22 month periods and analyzed patient and hospital characteristics associated with the likelihood of hospitalization. RESULTS: There were 81 051 ED visits coded for SI at 205 Illinois hospitals; 24.6% resulted in hospitalization. SI visits accounted for $785 million in charges and 145 160 hospital days over 66 months. ED SI visits increased 59% from 2016 through 2017 to 2019 through 2021, with a corresponding increase from 34.6% to 44.3% of SI principal diagnosis visits (both P < .001). Hospitalizations increased 57% between prepandemic fall 2019 and fall 2020 (P 5 .003). After controlling for demographic and clinical characteristics, youth were 84% less likely to be hospitalized if SI was their principal diagnosis and were more likely hospitalized if coded for severe mental illness, substance use, anxiety, or depression, or had ED visits to children’s or behavioral health hospitals. CONCLUSIONS: This study documents child ED SI visits in Illinois spiked in 2019, with an additional surge in hospitalizations during the pandemic. Rapidly rising hospital use may reflect worsening mental illness and continued difficulty in accessing low cost, high-quality outpatient mental health services.