ImportanceThe health care workforce continues to experience high rates of depression and anxiety. Finding ways to effectively support the mental health and well-being of health care workers is challenging.ObjectiveTo test the effectiveness of remote, pushed digital assessments and engagement to improve depression and anxiety among health care workers compared with usual care.Design, Setting, and ParticipantsThis was a 9-month randomized clinical trial with a 6-month intervention period. Participants were health care workers with self-reported daily access to a smartphone and at least 4 clinical hours per week. Participants were randomized to usual care or the intervention between January 2022 and March 2023. Data analyses were conducted between May and July 2023.InterventionsAll participants completed baseline, 6-month, and 9-month mental health, well-being, and burnout assessments. The control group had open access to a web-based mental health platform. Participants in the intervention group received monthly text messaging about mental health, mental health assessments, and linkages to care.Main Outcomes and MeasuresThe primary outcomes were mean change in depression and anxiety scores at 6 months from baseline. Secondary outcomes include mean change in well-being, burnout, and self-reported workplace productivity.ResultsIn this study, 1275 participants were randomized (642 [50.4%] to the intervention group and 633 [49.6%] to control group). Participants had a mean (SD) age of 38.6 (10.9) years, 1063 participants (83.4%) were female, 320 (25.1%) self-identified as Black, and 793 (62.2%) self-identified as White. Across the groups, the mean difference in depression score was significantly different at 6 months (−0.96 [95% CI, −1.52 to −0.40]) and at 9 months (−1.14 [95% CI, −1.69 to −0.58]). The mean difference in anxiety score from baseline to 6 months was statistically significantly larger for those in the intervention group vs usual care (−0.71 [95% CI, −1.25 to −0.17]) and held true at 9 months (−1.06 [95% CI, −1.59 to −0.52]).Conclusions and RelevanceIn a trial of health care workers, a proactive digital engagement strategy, including pushed text messaging, mobile mental health assessments, and connection to care, improved depression and anxiety over a 6-month period compared with simply making the same resources available for individuals to find and use.Trial RegistrationClinicalTrials.gov Identifier: NCT05028075