The COVID-19 pandemic accelerated telehealth to deliver psychiatric services. Continuation of psychiatric services for individuals with high clinical acuity was critical. This study examined attendance to rapidly deployed telehealth services for psychiatrically high-risk individuals receiving intensive outpatient program (IOP), primarily group-based psychotherapy services for adults and adolescents by race/ethnicity, insurance, and clinical treatment program within a large hospital-based outpatient psychiatric setting. Chi-square tests compared whether attendance rates for telehealth versus in-person IOP services varied by population group, race, insurance, and clinical program, using observational data of adolescent and adult patients treated between October 1, 2019, and July 31, 2020. Appointment attendance increased for telehealth versus in-person services for adolescents (χ ( = 1) = 27.49, < 0.0001) and adults (χ ( = 1) = 434.37, < 0.0001). For adults, increased appointment attendance for telehealth was observed across insurance type (Medicaid: +11.5%; Medicare: +13.79%; Commercial: +6.94%), race/ethnicity (+6.23% to +15.76% across groups), and for IOP groups across all five diagnostic treatment programs (between 7.59% and 15.9% increases across groups). Adolescent results were mixed; increased appointment attendance for telehealth was observed among commercially insured youth (+7.11%), but no differences were observed for Medicaid-insured youth. Non-Hispanic white youth had increased attendance for telehealth (+8.38%) and no differences were observed for non-Hispanic black youth. Decreases were found in telehealth attendance for Hispanic/Latinx youth (-13.49%). Rapidly deployed telehealth increased attendance to intensive services for psychiatrically high-risk individuals, particularly among adults and for adolescents with commercial insurance and non-Hispanic white youth. Trends among racial/ethnic and Medicaid-insured youth warrant further investigation regarding the potential for special challenges or vulnerabilities and advocacy needs. Findings highlight telehealth as an important tool in supporting availability of services for individuals with high levels of psychiatric acuity, particularly for group-based services, during the pandemic.