What difference do open educational resources (OER) make compared with publisher content (non-OER) when costs and instructors remain constant? A total of 215 community college students enrolled in online, introductory courses were randomly assigned to OER or non-OER sections and compared on retention at the tuition drop date, completion with a C or better, course completion, and mean final exam scores. Students in the OER sections were retained and persisted at a statistically significant higher rate, lending credibility to the findings of former studies regarding retention and persistence rates in courses taught with OER materials. No statistically significant differences were found on completion rates or final exam scores. OER course materials should be considered in broader initiatives for student success in community colleges.