The paper aims at understanding changes in the distribution and accumulation of intellectual capital by analyzing migrants' educational profiles across a sample of 303 U.S. counties. The results suggest that newcomers are better educated than the resident population, and the education gap is most pronounced for newcomers from other states. The results further suggest that the educational status of newcomers "in-migrants" is positively related to the educational status of the resident population "stayers", thus implying a further agglomeration of human capital across space. However, for interstate migrants the effect is context-dependent, playing a greater role in urban than in rural settings.