This quantitative study utilized secondary data from one large four-year, state university in the southwestern US. The relationship between registration time and academic performance was examined as well as the relationship between registration time and retention of first-time-in-college (FTIC) undergraduate students during their first semester of enrollment at the university. The differences between decided and undecided students were tested regarding students’ academic performance and retention of the same population. The study population for the fall 2011 semester included 6,739 freshmen, and the study population for the fall 2012 semester included 4,454 freshmen. Through multiple and logistic regression models, registration time was shown to statistically have a relationship with academic performance and retention (p < .05). Later registrants showed to have a negative relationship with GPA and were less likely to return the following spring semester. The explained variance (R2) for both measures of academic performance and retention along with descriptive statistics are also presented. A Mann Whitney U test and chi square test indicated that a statistically significant association between decided and undecided students exists for academic performance and retention (p < .05). Decided major students performed better as measured by semester GPA performance and were more likely to return the following spring semester. Recommendations and implications are issued regarding future research, policy, and practice.