The aim of this study was to examine students' (N = 579) achievement goal orientation profiles, the temporal stability of these profiles across the transition to upper secondary education, and profile differences in academic well-being (i.e., school value, school burnout, schoolwork engagement, satisfaction with educational choice). By means of latent profile analysis, four groups of students with distinct motivational profiles were identified: indifferent, success-oriented, mastery-oriented, and avoidance-oriented. Motivational profiles were relatively stable across the transition; half of the students displayed identical profiles over time and most of the changes in the group memberships were directed towards neighboring groups. Regarding group differences, indifferent and avoidance-oriented students showed less adaptive patterns of motivation and academic well-being than did mastery- and success-oriented students. Both mastery- and success-oriented students were highly engaged in studying and found their schoolwork meaningful, although success-oriented students' stronger concerns with performance seemed to make them more vulnerable to school burnout. (Contains 9 tables and 3 figures.)