Background: Substance use and mental health are two barriers to engagement in care and antiretroviral therapy (ART) adherence among youth and young adults living with HIV (YLWH). The consequences of suboptimal adherence in YLWH are increased risk of HIV transmission and a future generation of immunodeficient adults with drug-resistant virus. Methods: The Youth to Telehealth and Texting for Engagement in Care (Y2TEC) study was a pilot randomized crossover trial that examined the feasibility and acceptability of a novel video-counseling series and accompanying text messages aimed at mental health, substance use, and HIV care engagement for YLWH. The intervention consisted of twelve 20-30-min weekly video-counseling sessions focused on identifying and addressing barriers to HIV care, mental health, and substance use challenges. Participants completed quantitative surveys at baseline, 4 months, and 8 months. Feasibility and acceptability were evaluated using prespecified benchmarks. Results: Fifty YLWH aged 18-29 years living in the San Francisco Bay Area were enrolled. Eighty-six percent and 75% of participants were retained at 4 and 8 months, respectively. A total of 455 (76%) video-counseling sessions were completed. In 82% of sessions, participants responded that they strongly agreed/agreed with this statement: "I felt heard, understood, and respected by the counselor." In 81% of sessions, participants responded that they strongly agreed/agreed with this statement: "Overall, today's session was right for me." At baseline, among participants reporting mental health challenges, only 10% noted having ever received mental health services, and among those who reported substance use challenges, ∼19% reported ever receiving substance use services. After 4 months of the Y2TEC intervention, participants reported slightly higher ART adherence and HIV knowledge, decreased depression and anxiety, and reduced stigma related to mental health and substance use. Conclusions: The Y2TEC intervention using video-counseling and text messaging was feasible and acceptable for YLWH. ClinicalTrials.gov ID: NCT03681145.