OBJECTIVE: Project Extension for Community Healthcare Outcomes (Project ECHO©) addresses urban-rural disparities in access to specialist care by building primary care provider (PCP) capacity through tele-education. Evidence supporting the use of this model for mental health care is limited. Therefore, this study evaluated a mental health and addictions-focused ECHO program. Primary outcome measures were PCP knowledge and perceived self-efficacy. Secondary objectives included: satisfaction, engagement, and sense of professional isolation. PCP knowledge and self-efficacy were hypothesized to improve with participation. METHODS: Using Moore's evaluation framework, we evaluated the ECHO program on participant engagement, satisfaction, learning, and competence. A pre-post design and weekly questionnaires measured primary and secondary outcomes, respectively. RESULTS: Knowledge test performance and self-efficacy ratings improved post-ECHO (knowledge change was significant, p < 0.001, d = 1.13; self-efficacy approached significance; p = 0.056, d = 0.57). Attrition rate was low (7.7%) and satisfaction ratings were high across all domains, with spokes reporting reduced feelings of isolation. DISCUSSION: This is the first study to report objective mental health outcomes related to Project ECHO. The results indicate high-participant retention is achievable, and provide preliminary evidence for increased knowledge and self-efficacy. These findings suggest this intervention may improve mental health management in primary care.