In which types of postsecondary institutions are students enrolled? In fall 2015, more than 17 million undergraduates enrolled in U.S. colleges and universities. The vast majority (76 percent) attend public institutions, with enrollments nearly evenly divided between four-year and two-year colleges. Relatively few undergraduates (8 percent) attend for-profit institutions. Of those who attend for-profits, the majority attend four-year institutions. Overall, approximately 60 percent of undergraduates enroll in four-year colleges, and nearly 40 percent attended 2-year colleges. Very few (less than 2 percent) attend less-than-two-year postsecondary institutions.