Access to personal medical information promotes patient understanding of health issues and enables patient self-advocacy of healthcare needs. The advent of electronic medical record systems and the 2016 21st Century CURES Act promoted and encouraged patient access to personal medical information, yet technology-dependent modalities have often disadvantaged certain communities. We sought to evaluate whether disparities existed in access to patient portals at our institution, the main pediatric care provider in an area serving one million children. We evaluated the activation of patient portal accounts at our institution over the past decade (2010-2021). Portal activation data were analyzed by ethnic background and language preference and income information available based on primary home access location. Further, we evaluated portal activation rates over time and across institutional interventions. A logistic regression model was used to identify important demographic associations with portal account status. Over 1 million patients were served at our pediatric institution over the study period with 47.7% having ever activated their patient portals. Univariate analyses and ultimately logistic regression modeling demonstrated significant differences in portal activation by ethnicity (odds ratio (confidence interval):1.36 (1.34, 1.37)), language preference (1.39 (1.37, 1.40)), and median household income (1.00001 (1.00001, 1.00001)). Interim interventions were successful in improving portal activation rates. Overall, electronic medical record portal activation was less prevalent among Hispanic, non-English speakers, and patients living in communities with lower median household income. Opportunities for interventions exist to reduce healthcare disparities in these underserved communities.