Objective This study aims to understand whether higher use of a patient portal can have an impact on mental health functioning and recovery. Method A mixed methods approach was used for this study. In 2019–2021, patients with mental health diagnoses at outpatient clinics in an academic centre were invited to complete World Health Organization Disability Assessment Scale 12 (WHODAS-12) and Mental Health Recovery Measure surveys at baseline, 3 months, and 6 months after signing up for the portal. At the 3-month time point, patients were invited to a semistructured interview with a member of the team to contextualize the findings obtained from the surveys. Analytics data was also collected from the platform to understand usage patterns on the portal. Results Overall, 113 participants were included in the analysis. There was no significant change in mental health functioning and recovery scores over the 6-month period. However, suboptimal usage was observed as 46% of participants did not complete any tasks within the portal. Thirty-five participants had low use of the portal (1–9 interactions) and 18 participants had high usage (10+ interactions). There were also no differences in mental health functioning and recovery scores between low and high users of the portal. Qualitative interviews highlighted many opportunities where the portal can support overall functioning and mental health recovery. Conclusions Collectively, this study suggests that higher use of a portal had no impact, either positive or negative, on mental health outcomes. While it may offer convenience and improved patient satisfaction, adequate support is needed to fully enable these opportunities for patient care. As the type of interaction with the portal was not specifically addressed, future work should focus on looking at ways to support patient engagement and portal usage throughout their care journey.