Purpose - This exploratory study aims to examine how online mentoring was provided through social media to support potential first-generation Latino college students during their final year of high school and their transition into a two-year or four-year institution. Design/methodology/approach - Using a one-year qualitative study design, data were collected through interviews, surveys, and archived interactions on Facebook. Discourse analysis was used to code for types of social, informational, and emotional support provided. Findings - Findings suggest that online mentoring through social media is a support system that the focal students turned to primarily for informational support, rather than for social or emotional support, and its impact seems to be contingent on the existence of conventional mentoring structures of high school counsellors, peers, and family. Practical implications - High school counsellors and mentors in college outreach programs can leverage students' presence in social media forums such as Facebook to help structure informational support (application deadlines, financial aid forms, contact information for college outreach) to help students prepare for and transition into college. Social implications - The visibility and amplification of information delivered through social media provides an untapped resource for assisting first-generation college students in navigating the complex financial and logistical steps in transitioning to college. Its use as an additional tool for counsellors and mentors could increase matriculation and retention rates. Originality - High school counsellors and directors of college outreach and mentoring programs could draw on findings in this paper when considering ways to integrate innovative approaches to providing mentoring support.