As they navigate the social and academic expectations of a new college, transfer students commonly suffer "transfer shock," or a sudden drop in GPA. However, little is known about why some students suffer transfer shock, why some bounce back, and the consequences in terms of student retention. This analysis of over 25,000 transfer students (N = 25,000) at a large flagship university finds an average first-term drop of -0.30 GPA points, but the impact of this shock on student departure is dependent on initial GPA, the steepness of the drop, and the student's ability to rebound in their second term. To support transfer student retention and graduation, sending institutions can help students to pre-appraise the potential setback as normal and temporary, while receiving institutions can provide proactive outreach to transfers who arrive with a GPA below 2.0 or who suffer a GPA drop steeper than -0.50 in their first term.