Background Over 41 million people in the United States speak Spanish as their primary language, of which 16 million have limited English proficiency (LEP). It is well-established that language barriers contribute to health disparities and that the use of ad-hoc interpretation by untrained family members results in substandard care. We developed a novel interpreter training program for medical students to serve as in-person interpreters at a charitable, resident continuity clinic so as to overcome the language barrier in the delivery of healthcare to LEP patients. Methods The Medical Student Interpreter Training Program (MSITP) consists of three steps. First, fluent Spanish-speaking students shadowed a licensed interpreter. Second, students took a standardized phone exam to demonstrate language proficiency. Finally, students completed a three-hour training on the methodology and ethics of interpreting conducted by the Department of Interpreter Services. Results Pre- and post-tests were administered to assess students’ familiarity with the Interpreter Code of Ethics and interpreter skills. Familiarity with the Interpreter Code of Ethics increased significantly with all students reporting feeling comfortable (47%) or very comfortable (53%) after training. The pre- and post-tests included free response questions, which were administered to assess competence in the methodology and ethics of interpreting. The cohort’s aggregate score increased by 35% after the training (Wilcoxon signed rank z-score = 2.53; p = .01). Conclusions Implementing the MSITP resulted in an increased number of trained, Spanish-speaking interpreters available to provide their services to LEP patients at an affiliated charitable clinic and throughout the university hospital. Unlike other program models which are time and resource-intensive, this program is replicable and easily managed by volunteers. The MSITP is an effective model for training students as medical interpreters to ensure the delivery of quality healthcare for LEP patients.