While it is well documented that college freshmen gain weight, there is a dearth of studies examining critical time periods for this weight change. Freshmen living on campus (n = 103; 21M, 82F) visited the laboratory in August/September, November, January, February/March, and April/May. Measurements at each visit included: weight, waist circumference (WC), and body composition (% fat). Overall weight gain was 2.6 ± 3.1 kg, with most occurring during the first (1.4 ± 2.1 kg) and final (0.5 ± 1.5 kg; p<0.05 for all) two months of the academic year. WC did not change. Overall % fat gain was 1.7 ± 3.3% with most (1.1 ± 2.5%; p<0.01 for both) occurring in the final two months of the academic year. Changes in % fat were correlated with changes in WC (r = 0.464) and weight (r = 0.686; p<0.001 for both). Freshman weight gain can partially be attributed to accretion of fat warranting future investigations on targeted prevention programs focusing on behaviors early and late in the academic year.