There is a need for a better acknowledgement of the pre-and postmigration factors that influence postmigration psychological adaptation of ethnic migrants. In the present study, first, we examined the effects of pre-acculturative stress, anticipated sociocultural difficulties, and anticipated discrimination on ethnic migrants' (N = 153) psychological well-being in the postmigration stage. These pre-migration factors were expected to influence postmigration acculturation experiences (i.e., perceived acculturative stress, sociocultural difficulties, and discrimination), which, in turn, were expected to be decisive for postmigration well-being. Second, we examined how the concordance between these premigration and postmigration factors affects postmigration well-being. According to the first set of results, (1) the effect of anticipated sociocultural difficulties on psychological adaptation is mediated by perceived sociocultural difficulties and acculturative stress in the postmigration stage, and (2) the effects of preacculturative stress and anticipated discrimination are present in terms of their impact on subsequent postmigration experiences (stress and discrimination, respectively), which are further associated with postmigration well-being. The second set of results, in turn, shows that ethnic migrants' psychological adaptation is highest (1) when both anticipated and perceived sociocultural difficulties are low and correspond with each other (but not when they anticipated more sociocultural difficulties than they experienced after migration), (2) when they both anticipate and perceive low levels of ethnic discrimination, and (3) when their perceived acculturative stress after migration is lower than pre-acculturative stress. The implications of the results for premigration interventions are discussed.